diff --git a/cmd/tendermint/flags.go b/cmd/tendermint/flags.go
index cdc6c1b32..029e65ab7 100644
--- a/cmd/tendermint/flags.go
+++ b/cmd/tendermint/flags.go
@@ -30,7 +30,8 @@ func parseFlags(config cfg.Config, args []string) {
 	flags.BoolVar(&skipUPNP, "skip_upnp", config.GetBool("skip_upnp"), "Skip UPNP configuration")
 	flags.StringVar(&rpcLaddr, "rpc_laddr", config.GetString("rpc_laddr"), "RPC listen address. Port required")
 	flags.StringVar(&logLevel, "log_level", config.GetString("log_level"), "Log level")
-	flags.StringVar(&proxyApp, "proxy_app", config.GetString("proxy_app"), "Proxy app address")
+	flags.StringVar(&proxyApp, "proxy_app", config.GetString("proxy_app"),
+		"Proxy app address, or 'nilapp' or 'dummy' for local testing.")
 	flags.Parse(args)
 	if printHelp {
 		flags.PrintDefaults()
diff --git a/consensus/common_test.go b/consensus/common_test.go
index c5ae6b7b5..fad0969bf 100644
--- a/consensus/common_test.go
+++ b/consensus/common_test.go
@@ -13,9 +13,9 @@ import (
 	bc "github.com/tendermint/tendermint/blockchain"
 	"github.com/tendermint/tendermint/config/tendermint_test"
 	mempl "github.com/tendermint/tendermint/mempool"
-	"github.com/tendermint/tendermint/proxy"
 	sm "github.com/tendermint/tendermint/state"
 	"github.com/tendermint/tendermint/types"
+	tmspcli "github.com/tendermint/tmsp/client"
 
 	"github.com/tendermint/tmsp/example/counter"
 )
@@ -313,8 +313,8 @@ func newConsensusState(state *sm.State, pv *types.PrivValidator) *ConsensusState
 
 	// one for mempool, one for consensus
 	mtx, app := new(sync.Mutex), counter.NewCounterApplication(false)
-	proxyAppConnMem := proxy.NewLocalAppConn(mtx, app)
-	proxyAppConnCon := proxy.NewLocalAppConn(mtx, app)
+	proxyAppConnMem := tmspcli.NewLocalClient(mtx, app)
+	proxyAppConnCon := tmspcli.NewLocalClient(mtx, app)
 
 	// Make Mempool
 	mempool := mempl.NewMempool(proxyAppConnMem)
diff --git a/mempool/mempool_test.go b/mempool/mempool_test.go
index 16dd656f2..750f987da 100644
--- a/mempool/mempool_test.go
+++ b/mempool/mempool_test.go
@@ -6,8 +6,8 @@ import (
 	"testing"
 
 	"github.com/tendermint/tendermint/config/tendermint_test"
-	"github.com/tendermint/tendermint/proxy"
 	"github.com/tendermint/tendermint/types"
+	tmspcli "github.com/tendermint/tmsp/client"
 	"github.com/tendermint/tmsp/example/counter"
 )
 
@@ -20,8 +20,8 @@ func TestSerialReap(t *testing.T) {
 	app := counter.NewCounterApplication(true)
 	app.SetOption("serial", "on")
 	mtx := new(sync.Mutex)
-	appConnMem := proxy.NewLocalAppConn(mtx, app)
-	appConnCon := proxy.NewLocalAppConn(mtx, app)
+	appConnMem := tmspcli.NewLocalClient(mtx, app)
+	appConnCon := tmspcli.NewLocalClient(mtx, app)
 	mempool := NewMempool(appConnMem)
 
 	appendTxsRange := func(start, end int) {
diff --git a/node/node.go b/node/node.go
index c85cb8850..5369a68d6 100644
--- a/node/node.go
+++ b/node/node.go
@@ -25,6 +25,7 @@ import (
 	sm "github.com/tendermint/tendermint/state"
 	"github.com/tendermint/tendermint/types"
 	"github.com/tendermint/tendermint/version"
+	tmspcli "github.com/tendermint/tmsp/client"
 	"github.com/tendermint/tmsp/example/dummy"
 	"github.com/tendermint/tmsp/example/nil"
 )
@@ -244,11 +245,11 @@ func getProxyApp(addr string, hash []byte) (proxyAppConn proxy.AppConn) {
 	case "nilapp":
 		app := nilapp.NewNilApplication()
 		mtx := new(sync.Mutex)
-		proxyAppConn = proxy.NewLocalAppConn(mtx, app)
+		proxyAppConn = tmspcli.NewLocalClient(mtx, app)
 	case "dummy":
 		app := dummy.NewDummyApplication()
 		mtx := new(sync.Mutex)
-		proxyAppConn = proxy.NewLocalAppConn(mtx, app)
+		proxyAppConn = tmspcli.NewLocalClient(mtx, app)
 	default:
 		// Run forever in a loop
 		remoteApp, err := proxy.NewRemoteAppConn(addr)
diff --git a/proxy/app_conn.go b/proxy/app_conn.go
index 7311a07b6..f959d7b8c 100644
--- a/proxy/app_conn.go
+++ b/proxy/app_conn.go
@@ -2,23 +2,8 @@ package proxy
 
 import (
 	tmspcli "github.com/tendermint/tmsp/client"
-	tmsp "github.com/tendermint/tmsp/types"
 )
 
 type AppConn interface {
-	SetResponseCallback(tmspcli.Callback)
-	Error() error
-
-	EchoAsync(msg string) *tmspcli.ReqRes
-	FlushAsync() *tmspcli.ReqRes
-	AppendTxAsync(tx []byte) *tmspcli.ReqRes
-	CheckTxAsync(tx []byte) *tmspcli.ReqRes
-	CommitAsync() *tmspcli.ReqRes
-	SetOptionAsync(key string, value string) *tmspcli.ReqRes
-
-	InfoSync() (info string, err error)
-	FlushSync() error
-	CommitSync() (res tmsp.Result)
-	InitChainSync(validators []*tmsp.Validator) (err error)
-	EndBlockSync(height uint64) (changedValidators []*tmsp.Validator, err error)
+	tmspcli.Client
 }
diff --git a/proxy/local_app_conn.go b/proxy/local_app_conn.go
deleted file mode 100644
index c2cab0718..000000000
--- a/proxy/local_app_conn.go
+++ /dev/null
@@ -1,133 +0,0 @@
-package proxy
-
-import (
-	tmspcli "github.com/tendermint/tmsp/client"
-	tmsp "github.com/tendermint/tmsp/types"
-	"sync"
-)
-
-type localAppConn struct {
-	mtx *sync.Mutex
-	tmsp.Application
-	tmspcli.Callback
-}
-
-func NewLocalAppConn(mtx *sync.Mutex, app tmsp.Application) *localAppConn {
-	return &localAppConn{
-		mtx:         mtx,
-		Application: app,
-	}
-}
-
-func (app *localAppConn) SetResponseCallback(cb tmspcli.Callback) {
-	app.mtx.Lock()
-	defer app.mtx.Unlock()
-	app.Callback = cb
-}
-
-// TODO: change tmsp.Application to include Error()?
-func (app *localAppConn) Error() error {
-	return nil
-}
-
-func (app *localAppConn) EchoAsync(msg string) *tmspcli.ReqRes {
-	return app.callback(
-		tmsp.RequestEcho(msg),
-		tmsp.ResponseEcho(msg),
-	)
-}
-
-func (app *localAppConn) FlushAsync() *tmspcli.ReqRes {
-	// Do nothing
-	return NewReqRes(tmsp.RequestFlush(), nil)
-}
-
-func (app *localAppConn) SetOptionAsync(key string, value string) *tmspcli.ReqRes {
-	app.mtx.Lock()
-	log := app.Application.SetOption(key, value)
-	app.mtx.Unlock()
-	return app.callback(
-		tmsp.RequestSetOption(key, value),
-		tmsp.ResponseSetOption(log),
-	)
-}
-
-func (app *localAppConn) AppendTxAsync(tx []byte) *tmspcli.ReqRes {
-	app.mtx.Lock()
-	res := app.Application.AppendTx(tx)
-	app.mtx.Unlock()
-	return app.callback(
-		tmsp.RequestAppendTx(tx),
-		tmsp.ResponseAppendTx(res.Code, res.Data, res.Log),
-	)
-}
-
-func (app *localAppConn) CheckTxAsync(tx []byte) *tmspcli.ReqRes {
-	app.mtx.Lock()
-	res := app.Application.CheckTx(tx)
-	app.mtx.Unlock()
-	return app.callback(
-		tmsp.RequestCheckTx(tx),
-		tmsp.ResponseCheckTx(res.Code, res.Data, res.Log),
-	)
-}
-
-func (app *localAppConn) CommitAsync() *tmspcli.ReqRes {
-	app.mtx.Lock()
-	res := app.Application.Commit()
-	app.mtx.Unlock()
-	return app.callback(
-		tmsp.RequestCommit(),
-		tmsp.ResponseCommit(res.Code, res.Data, res.Log),
-	)
-}
-
-func (app *localAppConn) InfoSync() (info string, err error) {
-	app.mtx.Lock()
-	info = app.Application.Info()
-	app.mtx.Unlock()
-	return info, nil
-}
-
-func (app *localAppConn) FlushSync() error {
-	return nil
-}
-
-func (app *localAppConn) CommitSync() (res tmsp.Result) {
-	app.mtx.Lock()
-	res = app.Application.Commit()
-	app.mtx.Unlock()
-	return res
-}
-
-func (app *localAppConn) InitChainSync(validators []*tmsp.Validator) (err error) {
-	app.mtx.Lock()
-	if bcApp, ok := app.Application.(tmsp.BlockchainAware); ok {
-		bcApp.InitChain(validators)
-	}
-	app.mtx.Unlock()
-	return nil
-}
-
-func (app *localAppConn) EndBlockSync(height uint64) (changedValidators []*tmsp.Validator, err error) {
-	app.mtx.Lock()
-	if bcApp, ok := app.Application.(tmsp.BlockchainAware); ok {
-		changedValidators = bcApp.EndBlock(height)
-	}
-	app.mtx.Unlock()
-	return changedValidators, nil
-}
-
-//-------------------------------------------------------
-
-func (app *localAppConn) callback(req *tmsp.Request, res *tmsp.Response) *tmspcli.ReqRes {
-	app.Callback(req, res)
-	return NewReqRes(req, res)
-}
-
-func NewReqRes(req *tmsp.Request, res *tmsp.Response) *tmspcli.ReqRes {
-	reqRes := tmspcli.NewReqRes(req)
-	reqRes.Response = res
-	reqRes.SetDone()
-	return reqRes
-}
diff --git a/proxy/remote_app_conn.go b/proxy/remote_app_conn.go
index 094ef36bc..a593c4a8e 100644
--- a/proxy/remote_app_conn.go
+++ b/proxy/remote_app_conn.go
@@ -8,7 +8,7 @@ import (
 // the application in general is not meant to be interfaced
 // with concurrent callers.
 type remoteAppConn struct {
-	*tmspcli.Client
+	tmspcli.Client
 }
 
 func NewRemoteAppConn(addr string) (*remoteAppConn, error) {
diff --git a/proxy/remote_app_conn_test.go b/proxy/remote_app_conn_test.go
index dcb4fdc16..ab42b9943 100644
--- a/proxy/remote_app_conn_test.go
+++ b/proxy/remote_app_conn_test.go
@@ -76,12 +76,11 @@ func TestInfo(t *testing.T) {
 	} else {
 		t.Log("Connected")
 	}
-	proxy.Start()
-	data, err := proxy.InfoSync()
-	if err != nil {
+	res := proxy.InfoSync()
+	if res.IsErr() {
 		t.Errorf("Unexpected error: %v", err)
 	}
-	if data != "size:0" {
+	if string(res.Data) != "size:0" {
 		t.Error("Expected ResponseInfo with one element 'size:0' but got something else")
 	}
 }