diff --git a/CMakeLists.txt b/CMakeLists.txt
index b28ca0b9..007b234e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -40,6 +40,7 @@ option(WITH_TFM "Build with support for tomsfastmath" FALSE)
 option(WITH_GMP "Build with support for GNU Multi Precision Arithmetic Library" FALSE)
 set(MPI_PROVIDER "LTM" CACHE STRING "Build tests and demos against 'LTM', 'TFM' or 'GMP', default is LTM")
 option(BUILD_SHARED_LIBS "Build shared library and only the shared library if \"ON\", default is static" OFF)
+option(WITH_PTHREAD "Build with pthread support" FALSE)
 
 #-----------------------------------------------------------------------------
 # Add support for ccache if desired
@@ -164,8 +165,8 @@ if(WITH_LTM)
         target_compile_definitions(${PROJECT_NAME} PUBLIC USE_LTM)
     endif()
     target_link_libraries(${PROJECT_NAME} PUBLIC libtommath)
-    list(APPEND LTC_MPI_PROVIDERS_CFLAGS -DLTM_DESC)
-    list(APPEND LTC_MPI_PROVIDERS_LIBS -ltommath)
+    list(APPEND LTC_PKG_CONFIG_CFLAGS -DLTM_DESC)
+    list(APPEND LTC_PKG_CONFIG_LIBS -ltommath)
     list(APPEND LTC_DEBIAN_MPI_PROVIDER_DEPENDS libtommath-dev)
 endif()
 # tomsfastmath
@@ -177,8 +178,8 @@ if(WITH_TFM)
         target_compile_definitions(${PROJECT_NAME} PUBLIC USE_TFM)
     endif()
     target_link_libraries(${PROJECT_NAME} PUBLIC tomsfastmath)
-    list(APPEND LTC_MPI_PROVIDERS_CFLAGS -DTFM_DESC)
-    list(APPEND LTC_MPI_PROVIDERS_LIBS -ltfm)
+    list(APPEND LTC_PKG_CONFIG_CFLAGS -DTFM_DESC)
+    list(APPEND LTC_PKG_CONFIG_LIBS -ltfm)
     list(APPEND LTC_DEBIAN_MPI_PROVIDER_DEPENDS libtfm-dev)
 endif()
 # GNU MP
@@ -190,13 +191,30 @@ if(WITH_GMP)
         target_compile_definitions(${PROJECT_NAME} PUBLIC USE_GMP)
     endif()
     target_link_libraries(${PROJECT_NAME} PUBLIC ${GMP_LIBRARIES})
-    list(APPEND LTC_MPI_PROVIDERS_CFLAGS -DGMP_DESC)
-    list(APPEND LTC_MPI_PROVIDERS_LIBS -lgmp)
+    list(APPEND LTC_PKG_CONFIG_CFLAGS -DGMP_DESC)
+    list(APPEND LTC_PKG_CONFIG_LIBS -lgmp)
     list(APPEND LTC_DEBIAN_MPI_PROVIDER_DEPENDS libgmp-dev)
 endif()
 
-list(JOIN LTC_MPI_PROVIDERS_CFLAGS " " MPI_PROVIDERS_CFLAGS)
-list(JOIN LTC_MPI_PROVIDERS_LIBS " " MPI_PROVIDERS_LIBS)
+
+#-----------------------------------------------------------------------------
+# other options
+#-----------------------------------------------------------------------------
+
+if(WITH_PTHREAD)
+    set(THREADS_PREFER_PTHREAD_FLAG ON)
+    find_package(Threads REQUIRED)
+    if(CMAKE_USE_PTHREADS_INIT)
+        target_compile_definitions(${PROJECT_NAME} PUBLIC LTC_PTHREAD)
+        target_link_libraries(${PROJECT_NAME} PRIVATE Threads::Threads)
+        list(APPEND LTC_PKG_CONFIG_CFLAGS -DLTC_PTHREAD)
+    else()
+        message(SEND_ERROR "pthreads not supported. Reconfigure ${PROJECT_NAME} with -DWITH_PTHREAD=OFF.")
+    endif()
+endif()
+
+list(JOIN LTC_PKG_CONFIG_CFLAGS " " PKG_CONFIG_CFLAGS)
+list(JOIN LTC_PKG_CONFIG_LIBS " " PKG_CONFIG_LIBS)
 list(JOIN LTC_DEBIAN_MPI_PROVIDER_DEPENDS " " DEBIAN_MPI_PROVIDER_DEPENDS)
 
 #-----------------------------------------------------------------------------
diff --git a/libtomcrypt.pc.in b/libtomcrypt.pc.in
index ebc977d8..4ca6bbea 100644
--- a/libtomcrypt.pc.in
+++ b/libtomcrypt.pc.in
@@ -5,5 +5,5 @@ includedir=${prefix}/@CMAKE_INSTALL_INCLUDEDIR@/@PROJECT_NAME@
 Name: LibTomCrypt
 Description: public domain open source cryptographic toolkit
 Version: @PROJECT_VERSION@
-Libs: -L${libdir} -ltomcrypt @MPI_PROVIDERS_LIBS@
-Cflags: -I${includedir} @MPI_PROVIDERS_CFLAGS@
+Libs: -L${libdir} -ltomcrypt @PKG_CONFIG_LIBS@
+Cflags: -I${includedir} @PKG_CONFIG_CFLAGS@
diff --git a/makefile.shared b/makefile.shared
index 22e0edc3..ae8f2370 100644
--- a/makefile.shared
+++ b/makefile.shared
@@ -55,17 +55,24 @@ endif
 include makefile_include.mk
 
 ifneq ($(findstring -DLTM_DESC,$(LTC_CFLAGS)),)
-LTC_MPI_PROVIDERS_CFLAGS += -DLTM_DESC
-LTC_MPI_PROVIDERS_LIBS += -ltommath
+LTC_PKG_CONFIG_CFLAGS += -DLTM_DESC
+LTC_PKG_CONFIG_LIBS += -ltommath
 endif
 ifneq ($(findstring -DTFM_DESC,$(LTC_CFLAGS)),)
-LTC_MPI_PROVIDERS_CFLAGS += -DTFM_DESC
-LTC_MPI_PROVIDERS_LIBS += -ltfm
+LTC_PKG_CONFIG_CFLAGS += -DTFM_DESC
+LTC_PKG_CONFIG_LIBS += -ltfm
 endif
 ifneq ($(findstring -DGMP_DESC,$(LTC_CFLAGS)),)
-LTC_MPI_PROVIDERS_CFLAGS += -DGMP_DESC
-LTC_MPI_PROVIDERS_LIBS += -lgmp
+LTC_PKG_CONFIG_CFLAGS += -DGMP_DESC
+LTC_PKG_CONFIG_LIBS += -lgmp
 endif
+ifneq ($(findstring -DLTC_PTHREAD,$(LTC_CFLAGS)),)
+LTC_PKG_CONFIG_CFLAGS += -DLTC_PTHREAD
+endif
+
+# set PKG_CONFIG_CFLAGS and PKG_CONFIG_LIBS to what your environment requires
+LTC_PKG_CONFIG_CFLAGS += $(PKG_CONFIG_CFLAGS)
+LTC_PKG_CONFIG_LIBS += $(PKG_CONFIG_LIBS)
 
 #ciphers come in two flavours... enc+dec and enc
 src/ciphers/aes/aes_enc.o: src/ciphers/aes/aes.c src/ciphers/aes/aes_tab.c
@@ -95,8 +102,8 @@ $(foreach demo, $(strip $(DEMOS)), $(eval $(call DEMO_template,$(demo))))
 install: $(call print-help,install,Installs the library + headers + pkg-config file) .common_install
 	sed -e 's,^prefix=.*,prefix=$(PREFIX),' -e 's,^Version:.*,Version: $(VERSION_PC),' -e 's,^libdir=.*,libdir=$(LIBPATH),' \
 		-e 's,^includedir=.*,includedir=$(INCPATH),' \
-		-e 's,@MPI_PROVIDERS_LIBS@,$(LTC_MPI_PROVIDERS_LIBS),' \
-		-e 's,@MPI_PROVIDERS_CFLAGS@,$(LTC_MPI_PROVIDERS_CFLAGS),' libtomcrypt.pc.in > libtomcrypt.pc
+		-e 's,@PKG_CONFIG_LIBS@,$(LTC_PKG_CONFIG_LIBS),' \
+		-e 's,@PKG_CONFIG_CFLAGS@,$(LTC_PKG_CONFIG_CFLAGS),' libtomcrypt.pc.in > libtomcrypt.pc
 	install -p -d $(DESTDIR)$(LIBPATH)/pkgconfig
 	install -p -m 644 libtomcrypt.pc $(DESTDIR)$(LIBPATH)/pkgconfig/