diff --git a/examples/SpdyServer.cc b/examples/SpdyServer.cc
index 269e64c..846ed86 100644
--- a/examples/SpdyServer.cc
+++ b/examples/SpdyServer.cc
@@ -57,7 +57,7 @@ const std::string SPDYD_SERVER = "spdyd spdylay/"SPDYLAY_VERSION;
 } // namespace
 
 Config::Config(): verbose(false), daemon(false), port(0), data_ptr(0),
-                  spdy3_only(false)
+                  spdy3_only(false), verify_client(false)
 {}
 
 Request::Request(int32_t stream_id)
@@ -874,6 +874,15 @@ int next_proto_cb(SSL *s, const unsigned char **data, unsigned int *len,
 }
 } // namespace
 
+namespace {
+int verify_callback(int preverify_ok, X509_STORE_CTX *ctx)
+{
+  // We don't verify the client certificate. Just request it for the
+  // testing purpose.
+  return 1;
+}
+} // namespace
+
 int SpdyServer::run()
 {
   SSL_CTX *ssl_ctx;
@@ -900,7 +909,12 @@ int SpdyServer::run()
     std::cerr << "SSL_CTX_check_private_key failed." << std::endl;
     return -1;
   }
-
+  if(config_->verify_client) {
+    SSL_CTX_set_verify(ssl_ctx,
+                       SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE |
+                       SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
+                       verify_callback);
+  }
   // We speaks "spdy/2" and "spdy/3".
   std::pair<unsigned char*, size_t> next_proto;
   unsigned char proto_list[14];
diff --git a/examples/SpdyServer.h b/examples/SpdyServer.h
index 4aefde4..aaf262d 100644
--- a/examples/SpdyServer.h
+++ b/examples/SpdyServer.h
@@ -51,6 +51,7 @@ struct Config {
   spdylay_on_request_recv_callback on_request_recv_callback;
   void *data_ptr;
   bool spdy3_only;
+  bool verify_client;
   Config();
 };
 
diff --git a/examples/spdycat.cc b/examples/spdycat.cc
index 7319c73..7e1e446 100644
--- a/examples/spdycat.cc
+++ b/examples/spdycat.cc
@@ -63,6 +63,8 @@ struct Config {
   bool verbose;
   bool spdy3_only;
   int timeout;
+  std::string certfile;
+  std::string keyfile;
   Config():null_out(false), remote_name(false), verbose(false),
            spdy3_only(false), timeout(-1) {}
 };
@@ -152,6 +154,20 @@ int communicate(const std::string& host, uint16_t port,
     next_proto = "spdy/3";
   }
   setup_ssl_ctx(ssl_ctx, &next_proto);
+  if(!config.keyfile.empty()) {
+    if(SSL_CTX_use_PrivateKey_file(ssl_ctx, config.keyfile.c_str(),
+                                   SSL_FILETYPE_PEM) != 1) {
+      std::cerr << ERR_error_string(ERR_get_error(), 0) << std::endl;
+      return -1;
+    }
+  }
+  if(!config.certfile.empty()) {
+    if(SSL_CTX_use_certificate_chain_file(ssl_ctx,
+                                          config.certfile.c_str()) != 1) {
+      std::cerr << ERR_error_string(ERR_get_error(), 0) << std::endl;
+      return -1;
+    }
+  }
   SSL *ssl = SSL_new(ssl_ctx);
   if(!ssl) {
     std::cerr << ERR_error_string(ERR_get_error(), 0) << std::endl;
@@ -282,7 +298,7 @@ int run(char **uris, int n)
 
 void print_usage(std::ostream& out)
 {
-  out << "Usage: spdycat [-Onv3] [--timeout=seconds] [URI...]" << std::endl;
+  out << "Usage: spdycat [-Onv3] [-t=seconds] [--cert=CERT] [--key=KEY] [URI...]" << std::endl;
 }
 
 void print_help(std::ostream& out)
@@ -299,19 +315,25 @@ void print_help(std::ostream& out)
       << "                       filename. Not implemented yet.\n"
       << "    -3, --spdy3        Only use SPDY/3.\n"
       << "    -t, --timeout=N    Timeout each request after N seconds.\n"
-      << "\n"
+      << "    --cert=CERT        Use the specified client certificate file.\n"
+      << "                       The file must be in PEM format.\n"
+      << "    --key=KEY          Use the client private key file. The file\n"
+      << "                       must be in PEM format.\n"
       << std::endl;
 }
 
 int main(int argc, char **argv)
 {
   while(1) {
+    int flag;
     static option long_options[] = {
       {"verbose", no_argument, 0, 'v' },
       {"null-out", no_argument, 0, 'n' },
       {"remote-name", no_argument, 0, 'O' },
       {"spdy3", no_argument, 0, '3' },
       {"timeout", required_argument, 0, 't' },
+      {"cert", required_argument, &flag, 1 },
+      {"key", required_argument, &flag, 2 },
       {"help", no_argument, 0, 'h' },
       {0, 0, 0, 0 }
     };
@@ -341,6 +363,18 @@ int main(int argc, char **argv)
       break;
     case '?':
       exit(EXIT_FAILURE);
+    case 0:
+      switch(flag) {
+      case 1:
+        // cert option
+        config.certfile = optarg;
+        break;
+      case 2:
+        // key option
+        config.keyfile = optarg;
+        break;
+      }
+      break;
     default:
       break;
     }
diff --git a/examples/spdyd.cc b/examples/spdyd.cc
index f66a4a3..7f23506 100644
--- a/examples/spdyd.cc
+++ b/examples/spdyd.cc
@@ -61,6 +61,12 @@ void print_help(std::ostream& out)
       << "                       current working directory is changed to '/'.\n"
       << "                       Therefore if this option is used, -d option\n"
       << "                       must be specified.\n"
+      << "    -V, --verify-client\n"
+      << "                       The server sends a client certificate\n"
+      << "                       request. If the client did not return a\n"
+      << "                       certificate, the handshake is terminated.\n"
+      << "                       Currently, this option just requests a\n"
+      << "                       client certificate and does not verify it.\n"
       << "\n"
       << "    -d, --htdocs=PATH  Specify document root. If this option is not\n"
       << "                       specified, the document root is the current\n"
@@ -86,10 +92,11 @@ int main(int argc, char **argv)
       {"help", no_argument, 0, 'h' },
       {"verbose", no_argument, 0, 'v' },
       {"spdy3", no_argument, 0, '3' },
+      {"verify-client", no_argument, 0, 'V' },
       {0, 0, 0, 0 }
     };
     int option_index = 0;
-    int c = getopt_long(argc, argv, "Dd:hv3", long_options, &option_index);
+    int c = getopt_long(argc, argv, "DVd:hv3", long_options, &option_index);
     if(c == -1) {
       break;
     }
@@ -97,6 +104,9 @@ int main(int argc, char **argv)
     case 'D':
       config.daemon = true;
       break;
+    case 'V':
+      config.verify_client = true;
+      break;
     case 'd':
       config.htdocs = optarg;
       break;