diff --git a/src/libstore/build.hh b/src/libstore/build.hh
index ed83d678ec..52e7c9b9d5 100644
--- a/src/libstore/build.hh
+++ b/src/libstore/build.hh
@@ -21,9 +21,12 @@ Derivation derivationFromPath(const Path & drvPath);
 
 /* Place in `paths' the set of all store paths in the file system
    closure of `storePath'; that is, all paths than can be directly or
-   indirectly reached from it.  `paths' is not cleared. */
+   indirectly reached from it.  `paths' is not cleared.  If
+   `flipDirection' is true, the set of paths that can reach
+   `storePath' is returned; that is, the closures under the `referers'
+   relation instead of the `references' relation is returned. */
 void computeFSClosure(const Path & storePath,
-    PathSet & paths);
+    PathSet & paths, bool flipDirection = false);
 
 /* Place in `paths' the set of paths that are required to `realise'
    the given store path, i.e., all paths necessary for valid
diff --git a/src/libstore/misc.cc b/src/libstore/misc.cc
index dbb9273f79..802e576512 100644
--- a/src/libstore/misc.cc
+++ b/src/libstore/misc.cc
@@ -12,17 +12,20 @@ Derivation derivationFromPath(const Path & drvPath)
 
 
 void computeFSClosure(const Path & storePath,
-    PathSet & paths)
+    PathSet & paths, bool flipDirection)
 {
     if (paths.find(storePath) != paths.end()) return;
     paths.insert(storePath);
 
     PathSet references;
-    queryReferences(storePath, references);
+    if (flipDirection)
+        queryReferers(storePath, references);
+    else
+        queryReferences(storePath, references);
 
     for (PathSet::iterator i = references.begin();
          i != references.end(); ++i)
-        computeFSClosure(*i, paths);
+        computeFSClosure(*i, paths, flipDirection);
 }
 
 
diff --git a/src/nix-store/help.txt b/src/nix-store/help.txt
index deef23ff8f..35d5423cd8 100644
--- a/src/nix-store/help.txt
+++ b/src/nix-store/help.txt
@@ -4,7 +4,8 @@ nix-store [OPTIONS...] [ARGUMENTS...]
 
 Operations:
 
-  --realise / -r: build a Nix derivation
+  --realise / -r: ensure path validity; if a derivation, ensure that
+      validity of the outputs
   --add / -A: copy a path to the Nix store
   --query / -q: query information
 
@@ -27,9 +28,16 @@ Query flags:
   --outputs: query the output paths of a Nix derivation (default)
   --requisites / -R: print all paths necessary to realise a path
   --references: print all paths referenced by the given path
-  --referers: print all paths refering to the given path
+  --referers: print all paths directly refering to the given path
+  --referers-closure: print all paths (in)directly refering to the given path
   --graph: print a dot graph rooted at given ids
 
+Query switches (not applicable to all queries):
+
+  --use-output: perform query on output of derivation, not derivation itself
+  --force-realise: realise the path before performing the query
+  --include-outputs: in `-R' on a derivation, include requisites of outputs
+  
 Options:
 
   --verbose / -v: verbose operation (may be repeated)
diff --git a/src/nix-store/main.cc b/src/nix-store/main.cc
index addf9c7d0d..dc7a6de8b8 100644
--- a/src/nix-store/main.cc
+++ b/src/nix-store/main.cc
@@ -96,7 +96,8 @@ static void printPathSet(const PathSet & paths)
 /* Perform various sorts of queries. */
 static void opQuery(Strings opFlags, Strings opArgs)
 {
-    enum { qOutputs, qRequisites, qReferences, qReferers, qGraph } query = qOutputs;
+    enum { qOutputs, qRequisites, qReferences, qReferers,
+           qReferersClosure, qGraph } query = qOutputs;
     bool useOutput = false;
     bool includeOutputs = false;
     bool forceRealise = false;
@@ -107,6 +108,7 @@ static void opQuery(Strings opFlags, Strings opArgs)
         else if (*i == "--requisites" || *i == "-R") query = qRequisites;
         else if (*i == "--references") query = qReferences;
         else if (*i == "--referers") query = qReferers;
+        else if (*i == "--referers-closure") query = qReferersClosure;
         else if (*i == "--graph") query = qGraph;
         else if (*i == "--use-output" || *i == "-u") useOutput = true;
         else if (*i == "--force-realise" || *i == "-f") forceRealise = true;
@@ -128,7 +130,8 @@ static void opQuery(Strings opFlags, Strings opArgs)
 
         case qRequisites:
         case qReferences:
-        case qReferers: {
+        case qReferers:
+        case qReferersClosure: {
             PathSet paths;
             for (Strings::iterator i = opArgs.begin();
                  i != opArgs.end(); i++)
@@ -138,6 +141,7 @@ static void opQuery(Strings opFlags, Strings opArgs)
                     storePathRequisites(path, includeOutputs, paths);
                 else if (query == qReferences) queryReferences(path, paths);
                 else if (query == qReferers) queryReferers(path,  paths);
+                else if (query == qReferersClosure) computeFSClosure(path, paths, true);
             }
             printPathSet(paths);
             break;
diff --git a/tests/dependencies.sh b/tests/dependencies.sh
index fe4aa0c3c9..56cb1e4c38 100644
--- a/tests/dependencies.sh
+++ b/tests/dependencies.sh
@@ -20,4 +20,7 @@ echo "$deps" | grep -q "$outPath"
 if echo "$deps" | grep -q "dependencies-input-1"; then exit 1; fi
 
 # Input-2 is retained.
-echo "$deps" | grep -q "dependencies-input-2"
+input2OutPath=$(echo "$deps" | grep "dependencies-input-2")
+
+# The referers closure of input-2 should include outPath.
+$TOP/src/nix-store/nix-store -q --referers-closure "$input2OutPath" | grep "$outPath"