diff --git a/asl_rulebook2/webapp/content.py b/asl_rulebook2/webapp/content.py
index afcc008..4eba083 100644
--- a/asl_rulebook2/webapp/content.py
+++ b/asl_rulebook2/webapp/content.py
@@ -8,18 +8,28 @@ import glob
 from flask import jsonify, send_file, url_for, abort
 
 from asl_rulebook2.webapp import app
-from asl_rulebook2.webapp.utils import change_extn, slugify
+from asl_rulebook2.webapp.utils import slugify
 
-content_docs = None
+content_sets = None
+content_doc_index = None
 
 # ---------------------------------------------------------------------
 
-def load_content_docs( startup_msgs, logger ):
-    """Load the content documents from the data directory."""
+def load_content_sets( startup_msgs, logger ):
+    """Load the content from the data directory."""
+
+    # NOTE: A "content set" is an index file, together with one or more "content docs".
+    # A "content doc" is a PDF file, with an associated targets and/or footnote file.
+    # This architecture allows us to have:
+    # - a single index file that references content spread over multiple PDF's (e.g. the MMP eASLRB,
+    #   together with additional modules in separate PDF's (e.g. RB or KGP), until such time these
+    #   get included in the main eASLRB).
+    # - rules for completely separate modules (e.g. third-party modules) that are not included
+    #   in the MMP eASLRB index, and have their own index.
 
     # initialize
-    global content_docs
-    content_docs = {}
+    global content_sets
+    content_sets = {}
     dname = app.config.get( "DATA_DIR" )
     if not dname:
         return
@@ -27,7 +37,15 @@ def load_content_docs( startup_msgs, logger ):
         startup_msgs.error( "Invalid data directory.", dname )
         return
 
-    def load_file( fname, content_doc, key, on_error, binary=False ):
+    def load_content_doc( fname_stem, title ):
+        # load the content doc files
+        content_doc = { "title": title }
+        load_file( fname_stem+".targets", content_doc, "targets", startup_msgs.warning )
+        load_file( fname_stem+".footnotes", content_doc, "footnotes", startup_msgs.warning )
+        load_file( fname_stem+".pdf", content_doc, "content", startup_msgs.warning, binary=True )
+        return content_doc
+
+    def load_file( fname, save_loc, key, on_error, binary=False ):
         fname = os.path.join( dname, fname )
         if not os.path.isfile( fname ):
             return False
@@ -45,30 +63,68 @@ def load_content_docs( startup_msgs, logger ):
             on_error( "Couldn't load \"{}\".".format( os.path.basename(fname) ), str(ex) )
             return False
         # save the file data
-        content_doc[ key ] = data
+        save_loc[ key ] = data
         return True
 
-    # load each content doc
-    logger.info( "Loading content docs: %s", dname )
+    def find_assoc_cdocs( fname_stem ):
+        # find other content docs associated with the content set (names have the form "Foo (...)")
+        matches = set()
+        for fname in os.listdir( dname ):
+            if not fname.startswith( fname_stem ):
+                continue
+            fname = os.path.splitext( fname )[0]
+            fname = fname[len(fname_stem):].strip()
+            if fname.startswith( "(" ) and fname.endswith( ")" ):
+                matches.add( fname[1:-1] )
+        return matches
+
+    # load each content set
+    logger.info( "Loading content sets: %s", dname )
     fspec = os.path.join( dname, "*.index" )
     for fname in glob.glob( fspec ):
-        # load the main index file
         fname2 = os.path.basename( fname )
         logger.info( "- %s", fname2 )
+        # load the index file
         title = os.path.splitext( fname2 )[0]
-        content_doc = {
-            "_fname": fname,
-            "doc_id": slugify( title ),
+        cset_id = slugify( title )
+        content_set = {
+            "cset_id": cset_id,
             "title": title,
+            "content_docs": {},
+            "index_fname": fname,
         }
-        if not load_file( fname2, content_doc, "index", startup_msgs.error ):
+        if not load_file( fname2, content_set, "index", startup_msgs.error ):
             continue # nb: we can't do anything without an index file
-        # load any associated files
-        load_file( change_extn(fname2,".targets"), content_doc, "targets", startup_msgs.warning )
-        load_file( change_extn(fname2,".footnotes"), content_doc, "footnotes", startup_msgs.warning )
-        load_file( change_extn(fname2,".pdf"), content_doc, "content", startup_msgs.warning, binary=True )
-        # save the new content doc
-        content_docs[ content_doc["doc_id"] ] = content_doc
+        # load the main content doc
+        fname_stem = os.path.splitext( fname2 )[0]
+        content_doc = load_content_doc( fname_stem, fname_stem )
+        cdoc_id = cset_id # nb: because this the main content document
+        content_doc[ "cdoc_id" ] = cdoc_id
+        content_set[ "content_docs" ][ cdoc_id ] = content_doc
+        # load any associated content docs
+        for fname_stem2 in find_assoc_cdocs( fname_stem ):
+            # nb: we assume there's only one space between the two filename stems :-/
+            content_doc = load_content_doc(
+                "{} ({})".format( fname_stem, fname_stem2 ),
+                fname_stem2
+            )
+            cdoc_id2 = "{}!{}".format( cdoc_id, slugify(fname_stem2) )
+            content_doc[ "cdoc_id" ] = cdoc_id2
+            content_set[ "content_docs" ][ cdoc_id2 ] = content_doc
+        # save the new content set
+        content_sets[ content_set["cset_id"] ] = content_set
+
+# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+def _dump_content_sets():
+    """Dump the available content sets."""
+    for cset_id, cset in content_sets.items():
+        print( "=== {} ({}) ===".format( cset["title"], cset_id ) )
+        for cdoc_id, cdoc in cset["content_docs"].items():
+            print( "Content doc: {} ({})".format( cdoc["title"], cdoc_id ) )
+            for key in [ "targets", "footnotes", "content" ]:
+                if key in cdoc:
+                    print( "- {}: {}".format( key, len(cdoc[key]) ))
 
 # ---------------------------------------------------------------------
 
@@ -76,25 +132,29 @@ def load_content_docs( startup_msgs, logger ):
 def get_content_docs():
     """Return the available content docs."""
     resp = {}
-    for cdoc in content_docs.values():
-        cdoc2 = {
-            "doc_id": cdoc["doc_id"],
-            "title": cdoc["title"],
-        }
-        if "content" in cdoc:
-            cdoc2["url"] = url_for( "get_content", doc_id=cdoc["doc_id"] )
-        if "targets" in cdoc:
-            cdoc2["targets"] = cdoc["targets"]
-        resp[ cdoc["doc_id"] ] = cdoc2
+    for cset in content_sets.values():
+        for cdoc in cset["content_docs"].values():
+            cdoc2 = {
+                "cdoc_id": cdoc["cdoc_id"],
+                "parent_cset_id": cset["cset_id"],
+                "title": cdoc["title"],
+            }
+            if "content" in cdoc:
+                cdoc2["url"] = url_for( "get_content", cdoc_id=cdoc["cdoc_id"] )
+            if "targets" in cdoc:
+                cdoc2["targets"] = cdoc["targets"]
+            resp[ cdoc["cdoc_id"] ] = cdoc2
     return jsonify( resp )
 
 # ---------------------------------------------------------------------
 
-@app.route( "/content/<doc_id>" )
-def get_content( doc_id ):
+@app.route( "/content/<cdoc_id>" )
+def get_content( cdoc_id ):
     """Return the content for the specified document."""
-    cdoc = content_docs.get( doc_id )
-    if not cdoc or "content" not in cdoc:
-        abort( 404 )
-    buf = io.BytesIO( cdoc["content"] )
-    return send_file( buf, mimetype="application/pdf" )
+    for cset in content_sets.values():
+        for cdoc in cset["content_docs"].values():
+            if cdoc["cdoc_id"] == cdoc_id and "content" in cdoc:
+                buf = io.BytesIO( cdoc["content"] )
+                return send_file( buf, mimetype="application/pdf" )
+    abort( 404 )
+    return None # stupid pylint :-/
diff --git a/asl_rulebook2/webapp/search.py b/asl_rulebook2/webapp/search.py
index 2a4566e..c2348b3 100644
--- a/asl_rulebook2/webapp/search.py
+++ b/asl_rulebook2/webapp/search.py
@@ -85,7 +85,7 @@ def _do_search( args ):
     def highlight( n ):
          # NOTE: highlight() is an FTS extension function, and takes column numbers :-/
         return "highlight(searchable,{},'{}','{}')".format( n, _BEGIN_HIGHLIGHT, _END_HIGHLIGHT )
-    sql = "SELECT rowid,doc_id,sr_type,rank,{},{},{},{} FROM searchable".format(
+    sql = "SELECT rowid,cset_id,sr_type,rank,{},{},{},{} FROM searchable".format(
         highlight(2), highlight(3), highlight(4), highlight(5)
     )
     sql += " WHERE searchable MATCH ?"
@@ -106,7 +106,7 @@ def _do_search( args ):
             continue
         index_entry = _fts_index_entries[ row[0] ]
         result = {
-            "doc_id": row[1],
+            "cset_id": row[1],
             "sr_type": row[2],
             "_key": "{}:{}:{}".format( row[1], row[2], row[0] ),
             "_score": - row[3],
@@ -347,17 +347,17 @@ def init_search( startup_msgs, logger ):
     # the overall content, and also lets us do AND/OR queries across all searchable content.
     conn.execute(
         "CREATE VIRTUAL TABLE searchable USING fts5"
-        " ( doc_id, sr_type, title, subtitle, content, rulerefs, tokenize='porter unicode61' )"
+        " ( cset_id, sr_type, title, subtitle, content, rulerefs, tokenize='porter unicode61' )"
     )
 
     # load the searchable content
     logger.info( "Loading the search index..." )
     conn.execute( "DELETE FROM searchable" )
     curs = conn.cursor()
-    for cdoc in webapp_content.content_docs.values():
-        logger.info( "- Loading index file: %s", cdoc["_fname"] )
+    for cset in webapp_content.content_sets.values():
+        logger.info( "- Loading index file: %s", cset["index_fname"] )
         nrows = 0
-        for index_entry in cdoc["index"]:
+        for index_entry in cset["index"]:
             rulerefs = _RULEREF_SEPARATOR.join( r.get("caption","") for r in index_entry.get("rulerefs",[]) )
             # NOTE: We should really strip content before adding it to the search index, otherwise any HTML tags
             # will need to be included in search terms. However, this means that the content returned by a query
@@ -365,8 +365,8 @@ def init_search( startup_msgs, logger ):
             # but that means we would lose the highlighting of search terms that SQLite gives us. We opt to insert
             # the original content, since none of it should contain HTML, anyway.
             curs.execute(
-                "INSERT INTO searchable (doc_id,sr_type,title,subtitle,content,rulerefs) VALUES (?,?,?,?,?,?)", (
-                    cdoc["doc_id"], "index",
+                "INSERT INTO searchable (cset_id,sr_type,title,subtitle,content,rulerefs) VALUES (?,?,?,?,?,?)", (
+                    cset["cset_id"], "index",
                     index_entry.get("title"), index_entry.get("subtitle"), index_entry.get("content"), rulerefs
             ) )
             _fts_index_entries[ curs.lastrowid ] = index_entry
diff --git a/asl_rulebook2/webapp/startup.py b/asl_rulebook2/webapp/startup.py
index cf73ae6..4946271 100644
--- a/asl_rulebook2/webapp/startup.py
+++ b/asl_rulebook2/webapp/startup.py
@@ -6,7 +6,7 @@ from collections import defaultdict
 from flask import jsonify
 
 from asl_rulebook2.webapp import app
-from asl_rulebook2.webapp.content import load_content_docs
+from asl_rulebook2.webapp.content import load_content_sets
 from asl_rulebook2.webapp.search import init_search
 
 _logger = logging.getLogger( "startup" )
@@ -26,7 +26,7 @@ def init_webapp():
     _startup_msgs = StartupMsgs()
 
     # initialize the webapp
-    load_content_docs( _startup_msgs, _logger )
+    load_content_sets( _startup_msgs, _logger )
     init_search( _startup_msgs, _logger )
 
 # ---------------------------------------------------------------------
diff --git a/asl_rulebook2/webapp/static/ContentPane.js b/asl_rulebook2/webapp/static/ContentPane.js
index 53fa05e..8416578 100644
--- a/asl_rulebook2/webapp/static/ContentPane.js
+++ b/asl_rulebook2/webapp/static/ContentPane.js
@@ -8,14 +8,14 @@ gMainApp.component( "content-pane", {
 
     template: `
 <tabbed-pages ref="tabbedPages">
-    <tabbed-page v-for="doc in contentDocs" :tabId=doc.doc_id :caption=doc.title :key=doc.doc_id >
-        <content-doc :doc=doc />
+    <tabbed-page v-for="cdoc in contentDocs" :tabId=cdoc.cdoc_id :caption=cdoc.title :key=cdoc.cdoc_id >
+        <content-doc :cdoc=cdoc />
     </tabbed-page>
 </tabbed-pages>`,
 
     mounted() {
-        gEventBus.on( "show-target", (docId, target) => { //eslint-disable-line no-unused-vars
-            this.$refs.tabbedPages.activateTab( docId ) ; // nb: tabId == docId
+        gEventBus.on( "show-target", (cdocId, target) => { //eslint-disable-line no-unused-vars
+            this.$refs.tabbedPages.activateTab( cdocId ) ; // nb: tabId == cdocId
         } ) ;
     },
 
@@ -25,7 +25,7 @@ gMainApp.component( "content-pane", {
 
 gMainApp.component( "content-doc", {
 
-    props: [ "doc" ],
+    props: [ "cdoc" ],
     data() { return {
         target: null,
         noContent: gUrlParams.get( "no-content" ),
@@ -33,14 +33,17 @@ gMainApp.component( "content-doc", {
 
     template: `
 <div class="content-doc" :data-target=target >
-    <div v-if=noContent class="disabled"> Content disabled. <div v-if=target>target = {{target}}</div> </div>
-    <iframe v-else-if=doc.url :src=makeDocUrl />
+    <div v-if=noContent class="disabled">
+        <div style='margin-bottom:0.25em;'>&mdash;&mdash;&mdash; Content disabled &mdash;&mdash;&mdash; </div>
+        {{cdoc.title}} <div v-if=target> target = {{target}} </div>
+    </div>
+    <iframe v-else-if=cdoc.url :src=makeDocUrl />
     <div v-else class="disabled"> No content. </div>
 </div>`,
 
     created() {
-        gEventBus.on( "show-target", (docId, target) => {
-            if ( docId != this.doc.doc_id )
+        gEventBus.on( "show-target", (cdocId, target) => {
+            if ( cdocId != this.cdoc.cdoc_id )
                 return ;
             // FUDGE! We give the tab time to show itself before we scroll to the target.
             setTimeout( () => {
@@ -52,7 +55,7 @@ gMainApp.component( "content-doc", {
     computed: {
 
         makeDocUrl() {
-            let url = this.doc.url ;
+            let url = this.cdoc.url ;
             if ( this.target )
                 url += "#nameddest=" + this.target ;
             return url ;
diff --git a/asl_rulebook2/webapp/static/MainApp.js b/asl_rulebook2/webapp/static/MainApp.js
index edd681b..43e05e2 100644
--- a/asl_rulebook2/webapp/static/MainApp.js
+++ b/asl_rulebook2/webapp/static/MainApp.js
@@ -12,9 +12,8 @@ $(document).ready( () => {
     gMainApp.mount( "#main-app" ) ;
 } ) ;
 
-// FUDGE! Can't seem to get access to the content docs via gMainApp, so we make them available
-// to the rest of the program via this global variable :-/
-export let gContentDocs = null ;
+// FUDGE! Can't seem to get access to gMainApp member variables, so we make them available
+// to the rest of the program via global variables :-/
 export let gTargetIndex = null ;
 
 // --------------------------------------------------------------------
@@ -58,13 +57,13 @@ gMainApp.component( "main-app", {
                 // get the content docs
                 $.getJSON( gGetContentDocsUrl, (resp) => { //eslint-disable-line no-undef
                     if ( gUrlParams.get( "add-empty-doc" ) )
-                        resp["empty"] = { "doc_id": "empty", "title": "Empty document" } ; // nb: for testing porpoises
+                        resp["empty"] = { "cdoc_id": "empty", "title": "Empty document" } ; // nb: for testing porpoises
                     self.contentDocs = resp ;
                     self.installContentDocs( resp ) ;
-                    let docIds = Object.keys( resp ) ;
-                    if ( docIds.length > 0 ) {
+                    let cdocIds = Object.keys( resp ) ;
+                    if ( cdocIds.length > 0 ) {
                         Vue.nextTick( () => {
-                            gEventBus.emit( "show-target", docIds[0], null ) ; // FIXME! which one do we choose?
+                            gEventBus.emit( "show-target", cdocIds[0], null ) ; // FIXME! which one do we choose?
                         } ) ;
                     }
                     resolve() ;
@@ -77,8 +76,6 @@ gMainApp.component( "main-app", {
         },
 
         installContentDocs( contentDocs ) {
-            // install the content docs
-            gContentDocs = contentDocs ;
             // build an index of all the targets
             gTargetIndex = {} ;
             Object.values( contentDocs ).forEach( (cdoc) => {
@@ -88,7 +85,11 @@ gMainApp.component( "main-app", {
                     let key = target.toLowerCase() ;
                     if ( ! gTargetIndex[ key ] )
                         gTargetIndex[ key ] = [] ;
-                    gTargetIndex[ key ].push( [ cdoc.doc_id, target ] ) ;
+                    gTargetIndex[ key ].push( {
+                        cset_id: cdoc.parent_cset_id,
+                        cdoc_id: cdoc.cdoc_id,
+                        target: target
+                    } ) ;
                 }
             } ) ;
         },
diff --git a/asl_rulebook2/webapp/static/SearchPane.js b/asl_rulebook2/webapp/static/SearchPane.js
index 67d449b..a871eb1 100644
--- a/asl_rulebook2/webapp/static/SearchPane.js
+++ b/asl_rulebook2/webapp/static/SearchPane.js
@@ -1,5 +1,5 @@
 import { gMainApp, gEventBus } from "./MainApp.js" ;
-import { findTarget, fixupSearchHilites } from "./utils.js" ;
+import { findTargets, fixupSearchHilites } from "./utils.js" ;
 
 // --------------------------------------------------------------------
 
@@ -71,11 +71,11 @@ gMainApp.component( "search-results", {
             }
 
             // check if the query string is just a target
-            let docIds = findTarget( queryString ) ;
-            if ( docIds ) {
-                // yup - just show it directly
+            let targets = findTargets( queryString, null ) ;
+            if ( targets && targets.length > 0 ) {
+                // yup - just show it directly (first one, if multiple)
                 this.searchResults = null ;
-                gEventBus.emit( "show-target", docIds[0][0], docIds[0][1] ) ;
+                gEventBus.emit( "show-target", targets[0].cdoc_id, targets[0].target ) ;
                 onSearchDone() ;
                 return ;
             }
@@ -109,9 +109,9 @@ gMainApp.component( "search-results", {
                     const ruleids = resp[i].ruleids ;
                     if ( ! ruleids )
                         continue ;
-                    const targets = findTarget( ruleids[0] ) ;
-                    if ( targets ) {
-                        gEventBus.emit( "show-target", targets[0][0], targets[0][1] ) ;
+                    const targets = findTargets( ruleids[0], resp[i].cset_id ) ;
+                    if ( targets && targets.length > 0 ) {
+                        gEventBus.emit( "show-target", targets[0].cdoc_id, targets[0].target ) ;
                         break ;
                     }
                 }
diff --git a/asl_rulebook2/webapp/static/SearchResult.js b/asl_rulebook2/webapp/static/SearchResult.js
index eae3d80..79017d5 100644
--- a/asl_rulebook2/webapp/static/SearchResult.js
+++ b/asl_rulebook2/webapp/static/SearchResult.js
@@ -1,5 +1,5 @@
-import { gMainApp, gEventBus, gContentDocs, gUrlParams } from "./MainApp.js" ;
-import { fixupSearchHilites, hasHilite } from "./utils.js" ;
+import { gMainApp, gEventBus, gUrlParams } from "./MainApp.js" ;
+import { findTargets, fixupSearchHilites, hasHilite } from "./utils.js" ;
 
 // --------------------------------------------------------------------
 
@@ -23,12 +23,12 @@ gMainApp.component( "index-sr", {
         <div v-if=sr.content class="content" v-html=sr.content />
         <div v-if=makeSeeAlso v-html=makeSeeAlso class="see-also" />
         <div v-if=sr.ruleids class="ruleids" >
-            <ruleid v-for="rid in sr.ruleids" :docId=sr.doc_id :ruleId=rid :key=rid />
+            <ruleid v-for="rid in sr.ruleids" :csetId=sr.cset_id :ruleId=rid :key=rid />
         </div>
         <ul v-if=sr.rulerefs class="rulerefs" >
             <li v-for="rref in sr.rulerefs" v-show=showRuleref(rref) :key=rref >
                 <span v-if=rref.caption class="caption" v-html=fixupHilites(rref.caption) />
-                <ruleid v-for="rid in rref.ruleids" :docId=sr.doc_id :ruleId=rid :key=rid />
+                <ruleid v-for="rid in rref.ruleids" :csetId=sr.cset_id :ruleId=rid :key=rid />
             </li>
         </ul>
     </div>
@@ -103,9 +103,9 @@ gMainApp.component( "index-sr", {
 
 gMainApp.component( "ruleid", {
 
-    props: [ "docId", "ruleId" ],
+    props: [ "csetId", "ruleId" ],
     data() { return {
-        target: null,
+        cdocId: null, target: null,
     } ; },
 
     template: `<span class="ruleid" v-bind:class="{unknown:!target}">[<a v-if=target @click=onClick>{{ruleId}}</a><span v-else>{{ruleId}}</span>]</span>`,
@@ -119,16 +119,20 @@ gMainApp.component( "ruleid", {
             ruleId = ruleId.substring( 0, pos ) ;
         }
         // check if the rule is one we know about
-        if ( gContentDocs[this.docId] && gContentDocs[this.docId].targets ) {
-            if ( gContentDocs[this.docId].targets[ ruleId ] )
-                this.target = ruleId ;
+        let targets = findTargets( ruleId, this.csetId ) ;
+        if ( targets && targets.length > 0 ) {
+            // NOTE: We assume that targets are unique within a content set. This might not be true if MMP
+            // ever adds Chapter Z stuff to the main index, but we'll cross that bridge if and when we come to it.
+            // TBH, that stuff would probably be better off as a separate content set, anyway.
+            this.cdocId = targets[0].cdoc_id ;
+            this.target = ruleId ;
         }
     },
 
     methods: {
         onClick() {
             // show the target
-            gEventBus.emit( "show-target", this.docId, this.target ) ;
+            gEventBus.emit( "show-target", this.cdocId, this.target ) ;
         },
     },
 
diff --git a/asl_rulebook2/webapp/static/utils.js b/asl_rulebook2/webapp/static/utils.js
index ed72144..3153f6e 100644
--- a/asl_rulebook2/webapp/static/utils.js
+++ b/asl_rulebook2/webapp/static/utils.js
@@ -2,10 +2,13 @@ import { gTargetIndex, gUrlParams } from "./MainApp.js" ;
 
 // --------------------------------------------------------------------
 
-export function findTarget( target )
+export function findTargets( target, csetId )
 {
     // check if the target is known to us
-    return gTargetIndex[ target.toLowerCase() ] ;
+    let targets = gTargetIndex[ target.toLowerCase() ] ;
+    if ( targets && csetId )
+        targets = targets.filter( (m) => m.cset_id == csetId ) ;
+    return targets ;
 }
 
 // --------------------------------------------------------------------
diff --git a/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1 (linked).docx b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1 (linked).docx
new file mode 100644
index 0000000..4911030
Binary files /dev/null and b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1 (linked).docx differ
diff --git a/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1 (linked).pdf b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1 (linked).pdf
new file mode 100644
index 0000000..8cacf92
Binary files /dev/null and b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1 (linked).pdf differ
diff --git a/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1 (linked).targets b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1 (linked).targets
new file mode 100644
index 0000000..eb477bc
--- /dev/null
+++ b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1 (linked).targets	
@@ -0,0 +1,12 @@
+{
+
+"1b": { "caption": "Item 1b", "page_no": 1, "pos": [72,718] },
+"2b": { "caption": "Item 2b", "page_no": 1, "pos": [72,503] },
+"3b": { "caption": "Item 3b", "page_no": 1, "pos": [72,292] },
+
+"4b": { "caption": "Item 4b", "page_no": 2, "pos": [72,718] },
+"5b": { "caption": "Item 5b", "page_no": 2, "pos": [72,503] },
+"6b": { "caption": "Item 6b", "page_no": 2, "pos": [72,292] }
+
+}
+
diff --git a/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1.docx b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1.docx
new file mode 100644
index 0000000..c0e9939
Binary files /dev/null and b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1.docx differ
diff --git a/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1.index b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1.index
new file mode 100644
index 0000000..2eeabf4
--- /dev/null
+++ b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1.index	
@@ -0,0 +1,23 @@
+[
+
+{ "title": "Content Set 1",
+  "rulerefs": [
+    { "caption": "Main document", "ruleids": [
+        "1a", "2a", "3a", "4a", "5a", "6a"
+      ]
+    },
+    { "caption": "Linked document", "ruleids": [
+        "1b", "2b", "3b", "4b", "5b", "6b"
+      ]
+    }
+  ]
+},
+
+{ "title": "Unknown ruleid",
+  "content": "This ruleid belongs to Content Set 2, so shouldn't work in <i>this</i> content set.",
+  "rulerefs": [ {
+    "caption": "Incorrect ruleref", "ruleids": [ "cs2a" ]
+  } ]
+}
+
+]
diff --git a/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1.pdf b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1.pdf
new file mode 100644
index 0000000..231a367
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diff --git a/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1.targets b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1.targets
new file mode 100644
index 0000000..808ccc5
--- /dev/null
+++ b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 1.targets	
@@ -0,0 +1,11 @@
+{
+
+"1a": { "caption": "Item 1a", "page_no": 1, "pos": [72,718] },
+"2a": { "caption": "Item 2a", "page_no": 1, "pos": [72,503] },
+"3a": { "caption": "Item 3a", "page_no": 1, "pos": [72,292] },
+
+"4a": { "caption": "Item 4a", "page_no": 2, "pos": [72,718] },
+"5a": { "caption": "Item 5a", "page_no": 2, "pos": [72,503] },
+"6a": { "caption": "Item 6a", "page_no": 2, "pos": [72,292] }
+
+}
diff --git a/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 2.docx b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 2.docx
new file mode 100644
index 0000000..b98554b
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diff --git a/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 2.index b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 2.index
new file mode 100644
index 0000000..e54c26d
--- /dev/null
+++ b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 2.index	
@@ -0,0 +1,13 @@
+[
+
+{ "title": "Content Set 2",
+  "rulerefs": [
+    { "caption": "The only document", "ruleids": [
+        "cs2a", "cs2b", "cs2c", "cs2d", "cs2e", "cs2f"
+      ]
+    }
+  ]
+}
+
+]
+
diff --git a/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 2.pdf b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 2.pdf
new file mode 100644
index 0000000..74222eb
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diff --git a/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 2.targets b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 2.targets
new file mode 100644
index 0000000..fd49f28
--- /dev/null
+++ b/asl_rulebook2/webapp/tests/fixtures/content-sets/content set 2.targets	
@@ -0,0 +1,12 @@
+{
+
+"cs2a": { "caption": "Item 1", "page_no": 1, "pos": [72,718] },
+"cs2b": { "caption": "Item 2", "page_no": 1, "pos": [72,503] },
+"cs2c": { "caption": "Item 3", "page_no": 1, "pos": [72,292] },
+
+"cs2d": { "caption": "Item 4", "page_no": 2, "pos": [72,718] },
+"cs2e": { "caption": "Item 5", "page_no": 2, "pos": [72,503] },
+"cs2f": { "caption": "Item 6", "page_no": 2, "pos": [72,292] }
+
+}
+
diff --git a/asl_rulebook2/webapp/tests/test_search.py b/asl_rulebook2/webapp/tests/test_search.py
index a2132cf..4ae92b5 100644
--- a/asl_rulebook2/webapp/tests/test_search.py
+++ b/asl_rulebook2/webapp/tests/test_search.py
@@ -167,6 +167,60 @@ def test_target_search( webapp, webdriver ):
 
 # ---------------------------------------------------------------------
 
+def test_content_sets( webapp, webdriver ):
+    """Test how content sets are managed."""
+
+    # initialize
+    webapp.control_tests.set_data_dir( "content-sets" )
+    init_webapp( webapp, webdriver, add_empty_doc=1 )
+
+    # bring up all the targets
+    results = _do_search( "content" )
+    results = {
+        sr["title"]: [
+            [ rref["caption"], rref["ruleids"] ]
+            for rref in sr["rulerefs"]
+        ] for sr in results
+    }
+    assert results == {
+        "((Content)) Set 1": [
+            [ "Main document", [ "1a", "2a", "3a", "4a", "5a", "6a" ] ],
+            [ "Linked document", [ "1b", "2b", "3b", "4b", "5b", "6b" ] ],
+        ],
+        "((Content)) Set 2": [
+            [ "The only document", [ "cs2a", "cs2b", "cs2c", "cs2d", "cs2e", "cs2f" ] ]
+        ],
+        "Unknown ruleid": [
+            [ "Incorrect ruleref", [ "cs2a" ] ]
+        ],
+    }
+
+    # check that the ruleid links are enabled/disabled correctly
+    ruleid_elems = {}
+    for sr_elem in find_children( "#search-results .sr" ):
+        title = find_child( ".title", sr_elem ).text
+        for ruleid_elem in find_children( ".ruleid", sr_elem ):
+            link = find_child( "a", ruleid_elem )
+            if title == "Unknown ruleid":
+                assert link is None
+            else:
+                assert link
+                assert link.text not in ruleid_elems
+                ruleid_elems[ link.text ] = ruleid_elem
+
+    def do_test( ruleid, expected ):
+        ruleid_elems[ ruleid ].click()
+        wait_for( 2, lambda: _get_curr_target() == (expected, ruleid) )
+
+    # test clicking on ruleid targets
+    do_test( "4b", "content-set-1!linked" )
+    do_test( "1a", "content-set-1" )
+    do_test( "cs2d", "content-set-2" )
+    select_tabbed_page( "#content", "empty" )
+    do_test( "1b", "content-set-1!linked" )
+
+# ---------------------------------------------------------------------
+
 def test_make_fts_query_string():
     """Test generating the FTS query string."""