diff --git a/ChangeLog b/ChangeLog
index 243bd6b..e9be97b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -36,6 +36,10 @@
    * Clarify ECDSA documentation and improve the sample code to avoid
      misunderstandings and potentially dangerous use of the API. Pointed out
      by Jean-Philippe Aumasson.
+   * Add support for alternative implementation for ECDSA, controlled by new
+     configuration flag MBEDTLS_ECDSA_ALT in config.h.
+     Alternative Ecdsa is supported for implementation of `mbedtls_ecdsa_sign`
+     and `mbedtls_ecdsa_verify`.
 
 = mbed TLS 2.5.0 branch released 2017-05-17