diff --git a/db/btree.h b/db/btree.h
index d49db2a8729..5413b270d78 100644
--- a/db/btree.h
+++ b/db/btree.h
@@ -263,11 +263,15 @@ namespace mongo {
             return s;
         }
 
+        BSONObj prettyKey( const BSONObj &key ) const {
+            return key.replaceFieldNames( indexDetails.keyPattern() ).clientReadable();
+        }
+        
         virtual BSONObj prettyStartKey() const {
-            return startKey.replaceFieldNames( indexDetails.keyPattern() ).clientReadable();
+            return prettyKey( startKey );
         }
         virtual BSONObj prettyEndKey() const {
-            return endKey.replaceFieldNames( indexDetails.keyPattern() ).clientReadable();
+            return prettyKey( endKey );
         }
         
     private:
diff --git a/db/dbcommands.cpp b/db/dbcommands.cpp
index 5eaddaba180..6e68db5fe8b 100644
--- a/db/dbcommands.cpp
+++ b/db/dbcommands.cpp
@@ -798,6 +798,53 @@ namespace mongo {
         }
     } cmdFileMD5;
     
+    class CmdMedianKey : public Command {
+    public:
+        CmdMedianKey() : Command( "medianKey" ) {}
+        virtual bool slaveOk() { return true; }
+        virtual void help( stringstream &help ) const {
+            help << " example: { medianKey:\"blog.posts\", keyPattern:{x:1} min:{x:10}, max:{x:55} }";
+        }
+        bool run(const char *dbname, BSONObj& jsobj, string& errmsg, BSONObjBuilder& result, bool fromRepl ){
+            const char *ns = jsobj.getStringField( "medianKey" );
+            BSONObj keyPattern = jsobj.getObjectField( "keyPattern" );
+            BSONObj min = jsobj.getObjectField( "min" ).extractFieldsUnDotted( keyPattern );
+            BSONObj max = jsobj.getObjectField( "max" ).extractFieldsUnDotted( keyPattern );
+            if ( ns[ 0 ] == '\0' || keyPattern.isEmpty() || min.isEmpty() || max.isEmpty() ) {
+                errmsg = "invalid command syntax";
+                return false;
+            }
+            setClient( ns );
+            const IndexDetails *id = 0;
+            NamespaceDetails *d = nsdetails( ns );
+            for (int i = 0; i < d->nIndexes; i++ ) {
+                IndexDetails& ii = d->indexes[i];
+                if( ii.keyPattern().woCompare(keyPattern) == 0 ) {
+                    id = &ii;
+                    break;
+                }
+            }            
+            if ( !id ) {
+                errmsg = "no index found for specified keyPattern";
+                return false;
+            }
+            
+            Timer t;
+            int num = 0;
+            for( BtreeCursor c( *id, min, max, 1 ); c.ok(); c.advance(), ++num );
+            num /= 2;
+            BtreeCursor c( *id, min, max, 1 );
+            for( ; num; c.advance(), --num );
+            int ms = t.millis();
+            if ( ms > 100 ) {
+                out() << "Finding median for index: " << keyPattern << " between " << min << " and " << max << " took " << ms << "ms." << endl;
+            }
+            
+            result.append( "median", c.prettyKey( c.currKey() ) );
+            return true;
+        }
+    } cmdMedianKey;
+    
     extern map<string,Command*> *commands;
 
     /* TODO make these all command objects -- legacy stuff here
diff --git a/jstests/median.js b/jstests/median.js
new file mode 100644
index 00000000000..f90a91490f5
--- /dev/null
+++ b/jstests/median.js
@@ -0,0 +1,33 @@
+f = db.jstests_median;
+f.drop();
+
+f.ensureIndex( {i:1} );
+for( i = 0; i < 1000; ++i ) {
+    f.save( {i:i} );
+}
+
+assert.eq( 500, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1}, min:{i:0}, max:{i:999} } ).median.i );
+assert.eq( 0, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1}, min:{i:0}, max:{i:0} } ).median.i );
+assert.eq( 500, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1}, min:{i:500}, max:{i:500} } ).median.i );
+assert.eq( 1, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1}, min:{i:0}, max:{i:1} } ).median.i );
+assert.eq( 1, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1}, min:{i:0}, max:{i:2} } ).median.i );
+
+f.drop();
+f.ensureIndex( {i:1,j:-1} );
+for( i = 0; i < 100; ++i ) {
+    for( j = 0; j < 100; ++j ) {
+        f.save( {i:i,j:j} );
+    }
+}
+
+assert.eq( 50, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1,j:-1}, min:{i:0,j:0}, max:{i:99,j:0} } ).median.i );
+assert.eq( 0, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1,j:-1}, min:{i:0,j:0}, max:{i:0,j:0} } ).median.i );
+assert.eq( 50, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1,j:-1}, min:{i:50,j:0}, max:{i:50,j:0} } ).median.i );
+assert.eq( 1, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1,j:-1}, min:{i:0,j:0}, max:{i:1,j:0} } ).median.i );
+assert.eq( 1, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1,j:-1}, min:{i:0,j:0}, max:{i:2,j:0} } ).median.i );
+
+assert.eq( 49, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1,j:-1}, min:{i:0,j:99}, max:{i:0,j:0} } ).median.j );
+assert.eq( 44, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1,j:-1}, min:{i:0,j:49}, max:{i:0,j:40} } ).median.j );
+
+assert.eq( 10, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1,j:-1}, min:{i:10,j:50}, max:{i:11,j:75} } ).median.i );
+assert.eq( 12, db.runCommand( {medianKey:"test.jstests_median", keyPattern:{i:1,j:-1}, min:{i:10,j:50}, max:{i:11,j:75} } ).median.j );
diff --git a/mongo.xcodeproj/project.pbxproj b/mongo.xcodeproj/project.pbxproj
index c47ab2f4fd4..d9117af6249 100644
--- a/mongo.xcodeproj/project.pbxproj
+++ b/mongo.xcodeproj/project.pbxproj
@@ -246,6 +246,7 @@
 		93D9469F0F7ABB0600C3C768 /* repl6.js */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.javascript; path = repl6.js; sourceTree = "<group>"; };
 		93D948200F7BF4FA00C3C768 /* remove5.js */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.javascript; path = remove5.js; sourceTree = "<group>"; };
 		93D948210F7BF4FA00C3C768 /* shellfork.js */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.javascript; path = shellfork.js; sourceTree = "<group>"; };
+		93D949B40F7D2A7700C3C768 /* median.js */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.javascript; path = median.js; sourceTree = "<group>"; };
 		93E3C5310F704C9D0029011E /* repl4.js */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.javascript; path = repl4.js; sourceTree = "<group>"; };
 		93E3C5960F7149F40029011E /* repl5.js */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.javascript; path = repl5.js; sourceTree = "<group>"; };
 		93E727090F4B5B5B004F9B5D /* shardkey.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = shardkey.cpp; sourceTree = "<group>"; };
@@ -530,6 +531,7 @@
 		93A8D1D10F37544800C92B85 /* jstests */ = {
 			isa = PBXGroup;
 			children = (
+				93D949B40F7D2A7700C3C768 /* median.js */,
 				93D948200F7BF4FA00C3C768 /* remove5.js */,
 				93D948210F7BF4FA00C3C768 /* shellfork.js */,
 				93D19B300F5EF09C0084C329 /* clone */,