--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -114,7 +114,7 @@
 set(GR_LIBEXEC_DIR      libexec)
 set(GR_PKG_LIBEXEC_DIR  ${GR_LIBEXEC_DIR}/${CMAKE_PROJECT_NAME})
 set(GRC_BLOCKS_DIR      ${GR_PKG_DATA_DIR}/grc/blocks)
-set(SYSCONFDIR          "${CMAKE_INSTALL_PREFIX}/${GR_CONF_DIR}" CACHE PATH "System configuration directory")
+set(SYSCONFDIR          "/${GR_CONF_DIR}" CACHE PATH "System configuration directory")
 set(GR_PREFSDIR         ${SYSCONFDIR}/${CMAKE_PROJECT_NAME}/conf.d)
 
 OPTION(ENABLE_PERFORMANCE_COUNTERS "Enable block performance counters" OFF)
