diff --git a/CMakeLists.txt b/CMakeLists.txt
index 31b4040..f9ba53f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -241,3 +241,10 @@
                     ${CMAKE_CURRENT_BINARY_DIR}/DartConfiguration.tcl COPYONLY)
     endif()
 endif()
+
+message(WARNING "\
+\n ****************************************************************\
+\n **** Mbed Crypto is no longer being updated. *******************\
+\n **** Please use Mbed TLS instead. See README.md. ***************\
+\n ****************************************************************\
+")
diff --git a/Makefile b/Makefile
index 4fd7f8e..c5b42a5 100644
--- a/Makefile
+++ b/Makefile
@@ -77,6 +77,10 @@
 	-scripts/config.py get MBEDTLS_TEST_NULL_ENTROPY && ([ $$? -eq 0 ]) && \
 	    echo '$(NULL_ENTROPY_WARNING)'
 endif
+	-echo "****************************************************************"
+	-echo "**** Mbed Crypto is no longer being updated. *******************"
+	-echo "**** Please use Mbed TLS instead. See README.md. ***************"
+	-echo "****************************************************************"
 
 clean:
 	$(MAKE) -C library clean
diff --git a/include/mbedtls/check_config.h b/include/mbedtls/check_config.h
index c3a3830..df35a16 100644
--- a/include/mbedtls/check_config.h
+++ b/include/mbedtls/check_config.h
@@ -30,6 +30,10 @@
 #ifndef MBEDTLS_CHECK_CONFIG_H
 #define MBEDTLS_CHECK_CONFIG_H
 
+#if defined(MBEDTLS_DEPRECATED_WARNING)
+#warning "Mbed Crypto is no longer being updated. Please use Mbed TLS instead. See README.md."
+#endif
+
 /*
  * We assume CHAR_BIT is 8 in many places. In practice, this is true on our
  * target platforms, so not an issue, but let's just be extra sure.