diff --git a/CMakeLists.txt b/CMakeLists.txt
index 020049e1..7931ee6f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -131,6 +131,10 @@ if(CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR CMAKE_CXX_COMPILER_ID MATCHES "GNU")
     endif()
 endif()
 
+if(NOT APPLE AND NOT MSVC)
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pthread")
+endif()
+
 #
 # Declare source and header files.
 #