diff --git a/cmd/util/ech.go b/cmd/util/ech.go
index 32a93e8..2e457e8 100644
--- a/cmd/util/ech.go
+++ b/cmd/util/ech.go
@@ -10,7 +10,7 @@ import (
 )
 
 const (
-	ECHVersionDraft09 uint16 = 0xff09 // draft-ietf-tls-esni-09
+	ECHVersionDraft09 uint16 = 0xfe09 // draft-ietf-tls-esni-09
 )
 
 // ECHConfigTemplate defines the parameters for generating an ECH config and
@@ -83,7 +83,7 @@ func GenerateECHKey(template ECHConfigTemplate) (*ECHKey, error) {
 
 	secretKey, err := sk.MarshalBinary()
 	if err != nil {
-		return nil, fmt.Errorf("failed to marshal KEM secert key: %s", err)
+		return nil, fmt.Errorf("failed to marshal KEM secret key: %s", err)
 	}
 
 	var c cryptobyte.Builder
diff --git a/impl-endpoints/cloudflare-go/runner.go b/impl-endpoints/cloudflare-go/runner.go
index 73cff48..d16d6e9 100644
--- a/impl-endpoints/cloudflare-go/runner.go
+++ b/impl-endpoints/cloudflare-go/runner.go
@@ -3,6 +3,7 @@ package main
 import (
 	"crypto/tls"
 	"crypto/x509"
+	"encoding/base64"
 	"errors"
 	"flag"
 	"io/ioutil"
@@ -11,66 +12,158 @@ import (
 	"os"
 )
 
-func createBaseClientConfig() (*tls.Config, error) {
-	certPool := x509.NewCertPool()
+type testCase interface {
+	ClientConfig() (*tls.Config, error)
+	ClientConnectionHandler(*tls.Conn) error
+	ServerConfig() (*tls.Config, error)
+	ServerConnectionHandler(*tls.Conn) error
+}
+
+var baseServerConfig, baseClientConfig *tls.Config
+
+func init() {
+	// Setup the base client configuration.
 	pem, err := ioutil.ReadFile("/testdata/root.crt")
 	if err != nil {
-		return nil, err
+		log.Fatal(err)
 	}
+
+	certPool := x509.NewCertPool()
 	certPool.AppendCertsFromPEM(pem)
-	return &tls.Config{RootCAs: certPool}, nil
-}
+	baseClientConfig = &tls.Config{
+		RootCAs: certPool,
+	}
 
-func createBaseServerConfig() (*tls.Config, error) {
-	cert, err := tls.LoadX509KeyPair("/testdata/example.crt", "/testdata/example.key")
+	// Setup the base server configuration.
+	serverCert, err := tls.LoadX509KeyPair(
+		"/testdata/example.crt",
+		"/testdata/example.key",
+	)
 	if err != nil {
-		return nil, err
+		log.Fatal(err)
 	}
-	return &tls.Config{Certificates: []tls.Certificate{cert}}, nil
-}
 
-type testCase interface {
-	ClientConfig() (*tls.Config, error)
-	ClientConnectionHandler(*tls.Conn) error
-	ServerConfig() (*tls.Config, error)
-	ServerConnectionHandler(*tls.Conn) error
-}
+	clientFacingCert, err := tls.LoadX509KeyPair(
+		"/testdata/client_facing.crt",
+		"/testdata/client_facing.key",
+	)
+	if err != nil {
+		log.Fatal(err)
+	}
 
-type delegatedCredentialTestCase struct {
+	baseServerConfig = &tls.Config{
+		Certificates: []tls.Certificate{
+			serverCert,
+			clientFacingCert,
+		},
+	}
 }
 
-func (c delegatedCredentialTestCase) ClientConfig() (*tls.Config, error) {
-	config, err := createBaseClientConfig()
-	if err != nil {
-		return nil, err
-	}
+type testCaseDC struct{}
 
+func (t testCaseDC) ClientConfig() (*tls.Config, error) {
+	config := baseClientConfig.Clone()
 	config.SupportDelegatedCredential = true
 	return config, nil
 }
 
-func (c delegatedCredentialTestCase) ClientConnectionHandler(conn *tls.Conn) error {
+func (t testCaseDC) ServerConfig() (*tls.Config, error) {
+	config := baseClientConfig.Clone()
+	return config, nil
+}
+
+func (t testCaseDC) ClientConnectionHandler(conn *tls.Conn) error {
 	if conn.ConnectionState().VerifiedDC == nil {
 		return errors.New("Failed to verify a delegated credential")
 	}
 	return nil
 }
 
-func (c delegatedCredentialTestCase) ServerConfig() (*tls.Config, error) {
-	config, err := createBaseServerConfig()
+func (t testCaseDC) ServerConnectionHandler(conn *tls.Conn) error {
+	// TODO
+	return errors.New("NOT IMPLEMENTED")
+}
+
+type echTestResult struct {
+	serverStatus tls.EXP_EventECHServerStatus
+}
+
+func (r *echTestResult) eventHandler(event tls.EXP_Event) {
+	switch e := event.(type) {
+	case tls.EXP_EventECHServerStatus:
+		r.serverStatus = e
+	}
+}
+
+type testCaseECHAccept struct{}
+
+func (t testCaseECHAccept) ClientConfig() (*tls.Config, error) {
+	base64ECHConfigs, err := ioutil.ReadFile("/testdata/ech_configs")
 	if err != nil {
 		return nil, err
 	}
+
+	rawECHConfigs, err := base64.StdEncoding.DecodeString(string(base64ECHConfigs))
+	if err != nil {
+		return nil, err
+	}
+
+	echConfigs, err := tls.UnmarshalECHConfigs(rawECHConfigs)
+	if err != nil {
+		return nil, err
+	}
+
+	config := baseClientConfig.Clone()
+	config.ClientECHConfigs = echConfigs
+	config.ECHEnabled = true
 	return config, nil
 }
 
-func (c delegatedCredentialTestCase) ServerConnectionHandler(conn *tls.Conn) error {
-	// TODO
-	return errors.New("NOT IMPLEMENTED")
+func (t testCaseECHAccept) ServerConfig() (*tls.Config, error) {
+	base64ECHKeys, err := ioutil.ReadFile("/testdata/ech_key")
+	if err != nil {
+		return nil, err
+	}
+
+	rawECHKeys, err := base64.StdEncoding.DecodeString(string(base64ECHKeys))
+	if err != nil {
+		return nil, err
+	}
+
+	echKeys, err := tls.EXP_UnmarshalECHKeys(rawECHKeys)
+	if err != nil {
+		return nil, err
+	}
+
+	echProvider, err := tls.EXP_NewECHKeySet(echKeys)
+	if err != nil {
+		return nil, err
+	}
+
+	config := baseServerConfig.Clone()
+	config.ServerECHProvider = echProvider
+	config.ECHEnabled = true
+	return config, nil
+}
+
+func (t testCaseECHAccept) connectionHandler(conn *tls.Conn) error {
+	if !conn.ConnectionState().ECHAccepted {
+		return errors.New("ECH not accepted")
+	}
+	return nil
+}
+
+func (t testCaseECHAccept) ClientConnectionHandler(conn *tls.Conn) error {
+	return t.connectionHandler(conn)
+}
+
+func (t testCaseECHAccept) ServerConnectionHandler(conn *tls.Conn) error {
+	return t.connectionHandler(conn)
 }
 
 var testCaseHandlers = map[string]testCase{
-	"dc": delegatedCredentialTestCase{},
+	"dc":         testCaseDC{},
+	"ech-accept": testCaseECHAccept{},
 }
 
 func doClient(t testCase) error {
@@ -84,8 +177,8 @@ func doClient(t testCase) error {
 		return err
 	}
 	defer c.Close()
-	log.Print("Handshake completed")
 
+	log.Print("Handshake completed")
 	return t.ClientConnectionHandler(c)
 }
 
@@ -113,8 +206,8 @@ func doServer(t testCase) error {
 		return err
 	}
 	defer s.Close()
-	log.Print("Handshake completed")
 
+	log.Print("Handshake completed")
 	return t.ServerConnectionHandler(s)
 }
 
@@ -125,7 +218,7 @@ func main() {
 
 	handler, ok := testCaseHandlers[*testCase]
 	if !ok {
-		// Skip this test case
+		// Skip this test case.
 		os.Exit(64)
 	}