diff --git a/examples/spdylay_ssl.cc b/examples/spdylay_ssl.cc
index 56a57215..f6327cd5 100644
--- a/examples/spdylay_ssl.cc
+++ b/examples/spdylay_ssl.cc
@@ -407,13 +407,6 @@ void on_ctrl_recv_callback
   fflush(stdout);
 }
 
-namespace {
-const char* spdylay_strerror(int error_code)
-{
-  return "UNKNOWN";
-};
-} // namespace
-
 namespace {
 void dump_header(const uint8_t *head, size_t headlen)
 {
@@ -436,8 +429,9 @@ void on_ctrl_recv_parse_error_callback(spdylay_session *session,
                                        int error_code, void *user_data)
 {
   print_timer();
-  printf(" recv %s frame: Parse error [%s]\n", ctrl_names[type-1],
-         spdylay_strerror(error_code));
+  printf(" recv %s frame: Parse error\n", ctrl_names[type-1]);
+  print_frame_attr_indent();
+  printf("Error: %s\n", spdylay_strerror(error_code));
   dump_header(head, headlen);
   fflush(stdout);
 }
diff --git a/lib/includes/spdylay/spdylay.h b/lib/includes/spdylay/spdylay.h
index a5b2967d..f81064d5 100644
--- a/lib/includes/spdylay/spdylay.h
+++ b/lib/includes/spdylay/spdylay.h
@@ -1557,6 +1557,14 @@ uint8_t spdylay_session_get_pri_lowest(spdylay_session *session);
 int spdylay_session_fail_session(spdylay_session *session,
                                  uint32_t status_code);
 
+/**
+ * @function
+ *
+ * Returns string describing the |error_code|. The |error_code| must
+ * be one of the :enum:`spdylay_error`.
+ */
+const char* spdylay_strerror(int error_code);
+
 /**
  * @function
  *
diff --git a/lib/spdylay_helper.c b/lib/spdylay_helper.c
index 4504e470..a11bc734 100644
--- a/lib/spdylay_helper.c
+++ b/lib/spdylay_helper.c
@@ -71,3 +71,55 @@ int spdylay_reserve_buffer(uint8_t **buf_ptr, size_t *buflen_ptr,
   }
   return 0;
 }
+
+const char* spdylay_strerror(int error_code)
+{
+  switch(error_code) {
+  case SPDYLAY_ERR_INVALID_ARGUMENT:
+    return "Invalid argument";
+  case SPDYLAY_ERR_ZLIB:
+    return "Zlib error";
+  case SPDYLAY_ERR_UNSUPPORTED_VERSION:
+    return "Unsupported SPDY version";
+  case SPDYLAY_ERR_WOULDBLOCK:
+    return "Operation would block";
+  case SPDYLAY_ERR_PROTO:
+    return "Protocol error";
+  case SPDYLAY_ERR_INVALID_FRAME:
+    return "Invalid frame octets";
+  case SPDYLAY_ERR_EOF:
+    return "EOF";
+  case SPDYLAY_ERR_DEFERRED:
+    return "Data transfer deferred";
+  case SPDYLAY_ERR_STREAM_ID_NOT_AVAILABLE:
+    return "No more Stream ID available";
+  case SPDYLAY_ERR_STREAM_CLOSED:
+    return "Stream was already closed or invalid";
+  case SPDYLAY_ERR_STREAM_CLOSING:
+    return "Stream is closing";
+  case SPDYLAY_ERR_STREAM_SHUT_WR:
+    return "The transmission is not allowed for this stream";
+  case SPDYLAY_ERR_INVALID_STREAM_ID:
+    return "Stream ID is invalid";
+  case SPDYLAY_ERR_INVALID_STREAM_STATE:
+    return "Invalid stream state";
+  case SPDYLAY_ERR_DEFERRED_DATA_EXIST:
+    return "Another DATA frame has already been deferred";
+  case SPDYLAY_ERR_SYN_STREAM_NOT_ALLOWED:
+    return "SYN_STREAM is not allowed";
+  case SPDYLAY_ERR_GOAWAY_ALREADY_SENT:
+    return "GOAWAY has already been sent";
+  case SPDYLAY_ERR_INVALID_HEADER_BLOCK:
+    return "Invalid header block";
+  case SPDYLAY_ERR_INVALID_STATE:
+    return "Invalid state";
+  case SPDYLAY_ERR_GZIP:
+    return "Gzip error";
+  case SPDYLAY_ERR_NOMEM:
+    return "Out of memory";
+  case SPDYLAY_ERR_CALLBACK_FAILURE:
+    return "The user callback function failed";
+  default:
+    return "Unknown error code";
+  }
+}