diff --git a/CMakeLists.txt b/CMakeLists.txt
index 16600cc..03bb033 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -10,7 +10,7 @@ SET(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 PROJECT(FDPS_SPH)
 
-#Bring the headers, such as Student.h into the project
+#Bring the headers into the project
 INCLUDE_DIRECTORIES(src FDPS/src)
 
 SET(DEFAULT_BUILD_TYPE "Release")
@@ -18,19 +18,27 @@ SET(DEFAULT_BUILD_TYPE "Release")
 IF(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
 	MESSAGE(STATUS "Setting build type to '${DEFAULT_BUILD_TYPE}' as none was specified.")
 	SET(CMAKE_BUILD_TYPE "${DEFAULT_BUILD_TYPE}" CACHE
-      STRING "Choose the type of build." FORCE)
-  # Set the possible values of build type for cmake-gui
-  SET_PROPERTY(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS
-    "Debug" "Release" "MinSizeRel" "RelWithDebInfo")
+	    STRING "Choose the type of build." FORCE)
+	# Set the possible values of build type for cmake-gui
+	SET_PROPERTY(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS
+	             "Debug" "Release" "MinSizeRel" "RelWithDebInfo")
 ENDIF()
 
-SET(CMAKE_CXX_FLAGS "-DPARTICLE_SIMULATOR_THREAD_PARALLEL -fopenmp -DPARTICLE_SIMULATOR_ALL_64BIT_PRECISION -DFAST_COMM_FOR_2ND_EXCHANGE")
-SET(CMAKE_CXX_FLAGS_RELEASE "-O3 -ffast-math -funroll-loops")
+SET(CMAKE_CXX_FLAGS "-DPARTICLE_SIMULATOR_ALL_64BIT_PRECISION -DFAST_COMM_FOR_2ND_EXCHANGE -lm" CACHE STRING "compile flags" FORCE)
+SET(CMAKE_CXX_FLAGS_RELEASE "-O3 -ffast-math -funroll-loops" CACHE STRING "compile flags release mode" FORCE)
 
+SET(FDPS_USE_MPI OFF CACHE BOOL "Use MPI for parallelization.")
+
+IF(FDPS_USE_MPI)
+  SET(CMAKE_CXX_FLAGS "-DPARTICLE_SIMULATOR_MPI_PARALLEL ${CMAKE_CXX_FLAGS}" CACHE STRING "compile flags release model" FORCE)
+ELSE()
+  SET(CMAKE_CXX_FLAGS "-DPARTICLE_SIMULATOR_THREAD_PARALLEL -fopenmp ${CMAKE_CXX_FLAGS}" CACHE STRING "compile flags release model" FORCE)
+ENDIF()
 
 MESSAGE(STATUS "CMAKE_BUILD_TYPE:        ${CMAKE_BUILD_TYPE}")
 MESSAGE(STATUS "CMAKE_CXX_FLAGS:         ${CMAKE_CXX_FLAGS}")
 MESSAGE(STATUS "CMAKE_CXX_FLAGS_DEBUG:   ${CMAKE_CXX_FLAGS_DEBUG}")
 MESSAGE(STATUS "CMAKE_CXX_FLAGS_RELEASE: ${CMAKE_CXX_FLAGS_RELEASE}")
+MESSAGE(STATUS "FDPS_USE_MPI: ${FDPS_USE_MPI}")
 
 ADD_EXECUTABLE(sph.out src/main.cpp)