diff --git a/extra/benchmark/sockets/sockets.factor b/extra/benchmark/sockets/sockets.factor
index 40012e1638..36529facaa 100755
--- a/extra/benchmark/sockets/sockets.factor
+++ b/extra/benchmark/sockets/sockets.factor
@@ -1,5 +1,5 @@
 USING: io.sockets io.server io kernel math threads
-debugger tools.time prettyprint ;
+debugger tools.time prettyprint concurrency.combinators ;
 IN: benchmark.sockets
 
 : simple-server ( -- )
diff --git a/extra/calendar/model/model.factor b/extra/calendar/model/model.factor
index be98c7491e..aa295e0f75 100755
--- a/extra/calendar/model/model.factor
+++ b/extra/calendar/model/model.factor
@@ -1,6 +1,6 @@
 ! Copyright (C) 2008 Slava Pestov
 ! See http://factorcode.org/license.txt for BSD license.
-USING: calendar namespaces models threads init ;
+USING: calendar namespaces models threads kernel init ;
 IN: calendar.model
 
 SYMBOL: time
diff --git a/extra/channels/channels.factor b/extra/channels/channels.factor
index 07b5d2f5d5..01f810b8e3 100755
--- a/extra/channels/channels.factor
+++ b/extra/channels/channels.factor
@@ -19,7 +19,7 @@ GENERIC: from ( channel -- value )
     [ channel-senders push stop ] curry callcc0 ;
 
 : (to) ( value receivers -- )
-    delete-random schedule-thread-with yield ;
+    delete-random resume-with yield ;
 
 : notify ( continuation channel -- channel )
     [ channel-receivers push ] keep ;
diff --git a/extra/channels/remote/remote.factor b/extra/channels/remote/remote.factor
index 40a6df350b..b5a497b1fa 100755
--- a/extra/channels/remote/remote.factor
+++ b/extra/channels/remote/remote.factor
@@ -4,7 +4,7 @@
 ! Remote Channels
 USING: kernel init namespaces assocs arrays random
 sequences channels match concurrency.messaging
-concurrency.distributed ;
+concurrency.distributed threads ;
 IN: channels.remote
 
 <PRIVATE
@@ -24,27 +24,27 @@ PRIVATE>
     
 <PRIVATE
 
-MATCH-VARS: ?id ?value ;
+MATCH-VARS: ?from ?tag ?id ?value ;
 
 SYMBOL: no-channel
 
 : channel-process ( -- )
-    receive
-    {
-        { { ?from ?tag { to ?id ?value  } }
-          [ ?value ?id get-channel [ to f ] [ no-channel ] if* ?tag swap 2array ?from send ] }
-        { { ?from ?tag { from ?id  } }
-          [ ?id get-channel [ from ] [ no-channel ] if* ?tag swap 2array ?from send ] }
-    } match-cond 
-    channel-process ;
+    receive [
+        {
+            { { to ?id ?value  }
+            [ ?value ?id get-channel [ to f ] [ no-channel ] if* ] }
+            { { from ?id }
+            [ ?id get-channel [ from ] [ no-channel ] if* ] }
+        } match-cond
+    ] keep reply-synchronous ;
 
 PRIVATE>
 
 : start-channel-node ( -- )
     "remote-channels" get-process [
-      "remote-channels" 
-      [ channel-process ] "Remote channels" spawn
-      register-process 
+        "remote-channels" 
+        [ channel-process ] "Remote channels" spawn-server
+        register-process 
     ] unless ;
 
 TUPLE: remote-channel node id ;
@@ -52,12 +52,12 @@ TUPLE: remote-channel node id ;
 C: <remote-channel> remote-channel 
 
 M: remote-channel to ( value remote-channel -- )
-    dup >r [ \ to , remote-channel-id , , ] { } make r>
+    [ [ \ to , remote-channel-id , , ] { } make ] keep
     remote-channel-node "remote-channels" <remote-process> 
     send-synchronous no-channel = [ no-channel throw ] when ;
 
 M: remote-channel from ( remote-channel -- value )
-    dup >r [ \ from , remote-channel-id , ] { } make r>
+    [ [ \ from , remote-channel-id , ] { } make ] keep
     remote-channel-node "remote-channels" <remote-process> 
     send-synchronous dup no-channel = [ no-channel throw ] when* ;
 
diff --git a/extra/channels/sniffer/sniffer.factor b/extra/channels/sniffer/sniffer.factor
index 1502201225..cbf31c71e3 100755
--- a/extra/channels/sniffer/sniffer.factor
+++ b/extra/channels/sniffer/sniffer.factor
@@ -2,8 +2,8 @@
 ! See http://factorcode.org/license.txt for BSD license.
 !
 ! Wrap a sniffer in a channel
-USING: kernel channels concurrency io io.backend
-io.sniffer io.sniffer.backend system vocabs.loader ;
+USING: kernel channels io io.backend io.sniffer
+io.sniffer.backend system vocabs.loader ;
 
 : (sniff-channel) ( stream channel -- ) 
   4096 pick stream-read-partial over to (sniff-channel) ;
diff --git a/extra/concurrency/combinators/combinators.factor b/extra/concurrency/combinators/combinators.factor
new file mode 100755
index 0000000000..5e19baf393
--- /dev/null
+++ b/extra/concurrency/combinators/combinators.factor
@@ -0,0 +1,13 @@
+! Copyright (C) 2008 Slava Pestov.
+! See http://factorcode.org/license.txt for BSD license.
+USING: concurrency.futures concurrency.count-downs sequences
+kernel ;
+IN: concurrency.combinators
+
+: parallel-map ( seq quot -- newseq )
+    [ curry future ] curry map dup [ ?future ] change-each ;
+    inline
+
+: parallel-each ( seq quot -- )
+    "Parallel each" pick length <count-down>
+    [ [ spawn-stage ] 2curry each ] keep await ; inline
diff --git a/extra/concurrency/conditions/conditions.factor b/extra/concurrency/conditions/conditions.factor
new file mode 100755
index 0000000000..f94cfe6cca
--- /dev/null
+++ b/extra/concurrency/conditions/conditions.factor
@@ -0,0 +1,13 @@
+! Copyright (C) 2005, 2008 Chris Double, Slava Pestov.
+! See http://factorcode.org/license.txt for BSD license.
+USING: dlists threads kernel arrays sequences ;
+IN: concurrency.conditions
+
+: notify-1 ( dlist -- )
+    dup dlist-empty? [ pop-back resume ] [ drop ] if ;
+
+: notify-all ( dlist -- )
+    [ second resume ] dlist-slurp yield ;
+
+: wait ( queue timeout -- queue timeout )
+    [ 2array swap push-front ] suspend 3drop ; inline
diff --git a/extra/concurrency/count-downs/count-downs.factor b/extra/concurrency/count-downs/count-downs.factor
new file mode 100755
index 0000000000..122076eeb1
--- /dev/null
+++ b/extra/concurrency/count-downs/count-downs.factor
@@ -0,0 +1,32 @@
+! Copyright (C) 2008 Slava Pestov.
+! See http://factorcode.org/license.txt for BSD license.
+USING: dlists kernel math concurrency.promises
+concurrency.messaging ;
+IN: concurrency.count-downs
+
+! http://java.sun.com/j2se/1.5.0/docs/api/java/util/concurrent/CountDownLatch.html
+
+TUPLE: count-down n promise ;
+
+: <count-down> ( n -- count-down )
+    <dlist> count-down construct-boa ;
+
+: count-down ( count-down -- )
+    dup count-down-n dup zero? [
+        "Count down already done" throw
+    ] [
+        1- dup pick set-count-down-n
+        zero? [
+            t swap count-down-promise fulfill
+        ] [ drop ] if
+    ] if ;
+
+: await-timeout ( count-down timeout -- )
+    >r count-down-promise r> ?promise-timeout drop ;
+
+: spawn-stage ( quot name count-down -- )
+    count-down-promise
+    promise-mailbox spawn-linked-to drop ;
+
+: await ( count-down -- )
+    f await-timeout ;
diff --git a/extra/concurrency/distributed/distributed-docs.factor b/extra/concurrency/distributed/distributed-docs.factor
index 8f82d1aebf..ad9e392771 100755
--- a/extra/concurrency/distributed/distributed-docs.factor
+++ b/extra/concurrency/distributed/distributed-docs.factor
@@ -1,15 +1,7 @@
 USING: help.markup help.syntax concurrency.messaging ;
 IN: concurrency.distributed
 
-HELP: <remote-process>
-{ $values { "node" "a node object" } 
-          { "pid" "a process id" } 
-          { "remote-process" "the constructed remote-process object" } 
+HELP: local-node
+{ $values { "addrspec" "an address specifier" } 
 }
-{ $description "Constructs a proxy to a process running on another node. It can be used to send messages to the process it is acting as a proxy for." } 
-{ $see-also spawn send } ;
-
-HELP: localnode
-{ $values { "node" "a node object" } 
-}
-{ $description "Return the node the process is currently running on." } ;
+{ $description "Return the node the current thread is running on." } ;
diff --git a/extra/concurrency/distributed/distributed.factor b/extra/concurrency/distributed/distributed.factor
index 30587b35ac..2c54a872f7 100755
--- a/extra/concurrency/distributed/distributed.factor
+++ b/extra/concurrency/distributed/distributed.factor
@@ -6,8 +6,10 @@ namespaces kernel ;
 QUALIFIED: io.sockets
 IN: concurrency.distributed
 
+SYMBOL: local-node ( -- addrspec )
+
 : handle-node-client ( -- )
-    deserialize first2 thread send ;
+    deserialize first2 get-process send ;
 
 : (start-node) ( addrspecs addrspec -- )
     [
@@ -16,18 +18,19 @@ IN: concurrency.distributed
         [ handle-node-client ] with-server
     ] 2curry f spawn drop ;
 
-SYMBOL: local-node ( -- addrspec )
-
 : start-node ( port -- )
-    dup internet-server host-name rot <inet> (start-node) ;
+    dup internet-server io.sockets:host-name
+    rot io.sockets:<inet> (start-node) ;
 
-TUPLE: remote-thread pid node ;
+TUPLE: remote-process id node ;
 
-M: remote-thread send ( message thread -- )
-    { remote-thread-pid remote-thread-node } get-slots
+C: <remote-process> remote-process
+
+M: remote-process send ( message thread -- )
+    { remote-process-id remote-process-node } get-slots
     io.sockets:<client> [ 2array serialize ] with-stream ;
 
 M: thread (serialize) ( obj -- )
     thread-id local-node get-global
-    remote-thread construct-boa
+    <remote-process>
     (serialize) ;
diff --git a/extra/concurrency/futures/futures.factor b/extra/concurrency/futures/futures.factor
index fa8aba27fe..0a05d2d78e 100755
--- a/extra/concurrency/futures/futures.factor
+++ b/extra/concurrency/futures/futures.factor
@@ -1,25 +1,17 @@
 ! Copyright (C) 2005, 2008 Chris Double, Slava Pestov.
 ! See http://factorcode.org/license.txt for BSD license.
+USING: concurrency.promises concurrency.messaging kernel arrays
+continuations ;
 IN: concurrency.futures
 
 : future ( quot -- future )
     <promise> [
-        [
-            >r
-            [ t 2array ] compose
-            [ <linked> f 2array ] recover
-            r> fulfill
-        ] 2curry "Future" spawn drop
+        [ [ >r call r> fulfill ] 2curry "Future" ] keep
+        promise-mailbox spawn-linked-to drop
     ] keep ; inline
 
 : ?future-timeout ( future timeout -- value )
-    ?promise-timeout first2 [ rethrow ] unless ;
+    ?promise-timeout ;
 
 : ?future ( future -- value )
-    f ?future-timeout ;
-
-: parallel-map ( seq quot -- newseq )
-    [ curry future ] curry map [ ?future ] map ;
-
-: parallel-each ( seq quot -- )
-    [ f ] compose parallel-map drop ;
+    ?promise ;
diff --git a/extra/concurrency/locks/locks.factor b/extra/concurrency/locks/locks.factor
index 3a792768a7..50a62e3f6f 100755
--- a/extra/concurrency/locks/locks.factor
+++ b/extra/concurrency/locks/locks.factor
@@ -1,6 +1,7 @@
 ! Copyright (C) 2008 Slava Pestov.
 ! See http://factorcode.org/license.txt for BSD license.
-USING: dlists kernel threads continuations math ;
+USING: dlists kernel threads continuations math
+concurrency.conditions ;
 IN: concurrency.locks
 
 ! Simple critical sections
@@ -8,31 +9,26 @@ TUPLE: lock threads owner ;
 
 : <lock> <dlist> lock construct-boa ;
 
-: notify-1 ( dlist -- )
-    dup dlist-empty? [ pop-back resume ] [ drop ] if ;
-
 <PRIVATE
 
-: wait-for-lock ( lock -- )
-    [ swap lock-threads push-front ] suspend drop ;
-
-: acquire-lock ( lock -- )
-    dup lock-owner [ wait-for-lock ] when
+: acquire-lock ( lock timeout -- )
+    over lock-owner
+    [ 2dup >r lock-threads r> wait ] when drop
     self swap set-lock-owner ;
 
 : release-lock ( lock -- )
     f over set-lock-owner
     lock-threads notify-1 ;
 
-: do-lock ( lock quot acquire release -- )
-    >r >r over r> call over r> curry [ ] cleanup ; inline
+: do-lock ( lock timeout quot acquire release -- )
+    >r >r pick r> call over r> curry [ ] cleanup ; inline
 
 PRIVATE>
 
-: with-lock ( lock quot -- )
+: with-lock ( lock timeout quot -- )
     [ acquire-lock ] [ release-lock ] do-lock ; inline
 
-: with-reentrant-lock ( lock quot -- )
+: with-reentrant-lock ( lock timeout quot -- )
     over lock-owner self eq?
     [ nip call ] [ with-lock ] if ; inline
 
@@ -44,44 +40,39 @@ TUPLE: rw-lock readers writers reader# writer ;
 
 <PRIVATE
 
-: wait-for-read-lock ( lock -- )
-    [ swap lock-readers push-front ] suspend drop ;
-
-: acquire-read-lock ( lock -- )
-    dup rw-lock-writer [ dup wait-for-read-lock ] when
+: acquire-read-lock ( timeout lock -- )
+    dup rw-lock-writer
+    [ 2dup >r rw-lock-readers r> wait ] when drop
     dup rw-lock-reader# 1+ swap set-rw-lock-reader# ;
 
 : notify-writer ( lock -- )
-    lock-writers notify-1 ;
+    rw-lock-writers notify-1 ;
 
 : release-read-lock ( lock -- )
     dup rw-lock-reader# 1- dup pick set-rw-lock-reader#
-    zero? [ notify-writers ] [ drop ] if ;
-
-: wait-for-write-lock ( lock -- )
-    [ swap lock-writers push-front ] suspend drop ;
+    zero? [ notify-writer ] [ drop ] if ;
 
 : acquire-write-lock ( lock -- )
     dup rw-lock-writer over rw-lock-reader# 0 > or
-    [ dup wait-for-write-lock ] when
-    self over set-rw-lock-writer ;
+    [ 2dup >r rw-lock-writers r> wait ] when drop
+    self swap set-rw-lock-writer ;
 
 : release-write-lock ( lock -- )
     f over set-rw-lock-writer
     dup rw-lock-readers dlist-empty?
     [ notify-writer ] [ rw-lock-readers notify-all ] if ;
 
-: do-recursive-rw-lock ( lock quot quot' -- )
-    >r over rw-lock-writer self eq? [ nip call ] r> if ; inline
+: do-recursive-rw-lock ( lock timeout quot quot' -- )
+    >r pick rw-lock-writer self eq? [ 2nip call ] r> if ; inline
 
 PRIVATE>
 
-: with-read-lock ( lock quot -- )
+: with-read-lock ( lock timeout quot -- )
     [
         [ acquire-read-lock ] [ release-read-lock ] do-lock
     ] do-recursive-rw-lock ; inline
 
-: with-write-lock ( lock quot -- )
+: with-write-lock ( lock timeout quot -- )
     [
         [ acquire-write-lock ] [ release-write-lock ] do-lock
     ] do-recursive-rw-lock ; inline
diff --git a/extra/concurrency/messaging/messaging.factor b/extra/concurrency/messaging/messaging.factor
index 220be64364..e7a860495f 100755
--- a/extra/concurrency/messaging/messaging.factor
+++ b/extra/concurrency/messaging/messaging.factor
@@ -6,7 +6,7 @@
 IN: concurrency.messaging
 USING: dlists threads sequences continuations
 namespaces random math quotations words kernel arrays assocs
-init system ;
+init system concurrency.conditions ;
 
 TUPLE: mailbox threads data ;
 
@@ -16,29 +16,22 @@ TUPLE: mailbox threads data ;
 : mailbox-empty? ( mailbox -- bool )
     mailbox-data dlist-empty? ;
 
-: notify-all ( dlist -- )
-    [ second resume ] dlist-slurp yield ;
-
 : mailbox-put ( obj mailbox -- )
     [ mailbox-data push-front ] keep
     mailbox-threads notify-all ;
 
 <PRIVATE
 
-: mailbox-wait ( mailbox timeout -- mailbox timeout )
-    [ 2array swap mailbox-threads push-front ] suspend drop ;
-    inline
-
 : block-unless-pred ( pred mailbox timeout -- )
     2over mailbox-data dlist-contains? [
         3drop
     ] [
-        mailbox-wait block-unless-pred
+        2dup mailbox-threads wait block-unless-pred
     ] if ; inline
 
 : block-if-empty ( mailbox timeout -- mailbox )
     over mailbox-empty? [
-        mailbox-wait block-if-empty
+        2dup mailbox-threads wait block-if-empty
     ] [
         drop
     ] if ;
@@ -104,8 +97,12 @@ M: thread send ( message thread -- )
 : rethrow-linked ( error supervisor -- )
     >r <linked> r> send ;
 
+: spawn-linked-to ( quot name mailbox -- thread )
+    [ >r <linked> r> mailbox-put ] curry <thread>
+    [ (spawn) ] keep ;
+
 : spawn-linked ( quot name -- thread )
-    self [ rethrow-linked ] curry <thread> [ (spawn) ] keep ;
+    mailbox spawn-linked-to ;
 
 TUPLE: synchronous data sender tag ;
 
@@ -124,3 +121,21 @@ TUPLE: reply data tag ;
 
 : reply-synchronous ( message synchronous -- )
     [ <reply> ] keep synchronous-sender send ;
+
+<PRIVATE
+
+: remote-processes ( -- hash )
+   \ remote-processes get-global ;
+
+PRIVATE>
+
+: register-process ( name process -- )
+    swap remote-processes set-at ;
+
+: unregister-process ( name -- )
+    remote-processes delete-at ;
+
+: get-process ( name -- process )
+    dup remote-processes at [ ] [ thread ] ?if ;
+
+\ remote-processes global [ H{ } assoc-like ] change-at
diff --git a/extra/concurrency/promises/promises.factor b/extra/concurrency/promises/promises.factor
index ecaa722b11..6610a8c7ed 100755
--- a/extra/concurrency/promises/promises.factor
+++ b/extra/concurrency/promises/promises.factor
@@ -1,5 +1,7 @@
 ! Copyright (C) 2005, 2008 Chris Double, Slava Pestov.
 ! See http://factorcode.org/license.txt for BSD license.
+USING: concurrency.messaging concurrency.messaging.private
+kernel ;
 IN: concurrency.promises
 
 TUPLE: promise mailbox ;
@@ -18,7 +20,8 @@ TUPLE: promise mailbox ;
     ] if ;
 
 : ?promise-timeout ( promise timeout -- result )
-    >r promise-mailbox r> block-if-empty mailbox-peek ;
+    >r promise-mailbox r> block-if-empty
+    mailbox-peek ?linked ;
 
 : ?promise ( promise -- result )
     f ?promise-timeout ;
diff --git a/extra/concurrency/semaphores/semaphores.factor b/extra/concurrency/semaphores/semaphores.factor
index 7bfaf4c1ce..4afa02307a 100755
--- a/extra/concurrency/semaphores/semaphores.factor
+++ b/extra/concurrency/semaphores/semaphores.factor
@@ -1,3 +1,6 @@
+! Copyright (C) 2008 Slava Pestov.
+! See http://factorcode.org/license.txt for BSD license.
+USING: dlists kernel threads math ;
 IN: concurrency.semaphores
 
 TUPLE: semaphore count threads ;
diff --git a/extra/io/server/server.factor b/extra/io/server/server.factor
index f988b1eeab..160af21661 100755
--- a/extra/io/server/server.factor
+++ b/extra/io/server/server.factor
@@ -3,7 +3,7 @@
 USING: io io.sockets io.files logging continuations kernel
 math math.parser namespaces parser sequences strings
 prettyprint debugger quotations calendar
-threads concurrency.futures ;
+threads concurrency.combinators ;
 
 IN: io.server
 
diff --git a/extra/webapps/planet/planet.factor b/extra/webapps/planet/planet.factor
index e4820c0d59..062f6dbce2 100755
--- a/extra/webapps/planet/planet.factor
+++ b/extra/webapps/planet/planet.factor
@@ -1,6 +1,6 @@
-USING: sequences rss arrays concurrency.futures kernel sorting
-html.elements io assocs namespaces math threads
-vocabs html furnace http.server.templating calendar math.parser
+USING: sequences rss arrays concurrency.combinators kernel
+sorting html.elements io assocs namespaces math threads vocabs
+html furnace http.server.templating calendar math.parser
 splitting continuations debugger system http.server.responders
 xml.writer prettyprint logging ;
 IN: webapps.planet