diff --git a/CMakeLists.txt b/CMakeLists.txt
index 83c28bec65f36a61e9aa55dae92725329d1d2818..8fa5a77758fe497cb7c1783bc6eec3c4db1386a5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -17,7 +17,7 @@ CMAKE_MINIMUM_REQUIRED(VERSION 2.8 FATAL_ERROR)
 INCLUDE(CheckCXXCompilerFlag)
 CHECK_CXX_COMPILER_FLAG("-std=c++11" COMPILER_SUPPORTS_CXX11)
 IF(COMPILER_SUPPORTS_CXX11)
-  SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
+  SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -O3")
 ELSE()
   MESSAGE(STATUS "The compiler ${CMAKE_CXX_COMPILER} has no C++11 support. Please use a different C++ compiler.")
 ENDIF()