diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0b12053..5d967fb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -46,12 +46,16 @@ target_compile_features(xsimd INTERFACE cxx_std_14)
 # developed or is vendored.
 # Otherwise (if an install is performed), this will be handled in the user
 # cmake script (xsimdConfig.cmake).
+set(XSIMD_PKGCONFIG_REQUIRES "")
+set(XSIMD_PKGCONFIG_CFLAGS "")
 if(ENABLE_XTL_COMPLEX OR XSIMD_ENABLE_XTL_COMPLEX)
     find_package(xtl 0.8.0 REQUIRED)
     target_link_libraries(xsimd INTERFACE $<BUILD_INTERFACE:xtl>)
     target_compile_definitions(xsimd INTERFACE
         $<BUILD_INTERFACE:XSIMD_ENABLE_XTL_COMPLEX=1>
     )
+    set(XSIMD_PKGCONFIG_REQUIRES "xtl >= 0.8.0")
+    set(XSIMD_PKGCONFIG_CFLAGS "-DXSIMD_ENABLE_XTL_COMPLEX=1")
 endif()
 
 if(BUILD_TESTS)
diff --git a/xsimd.pc.in b/xsimd.pc.in
index 0ab1a8a..d3c4daf 100644
--- a/xsimd.pc.in
+++ b/xsimd.pc.in
@@ -5,4 +5,5 @@ includedir=@CMAKE_INSTALL_FULL_INCLUDEDIR@
 Name: xsimd
 Description: xsimd provides a unified means for using SIMD features for library authors..
 Version: @xsimd_VERSION@
-Cflags: -I${includedir}
+Requires: @XSIMD_PKGCONFIG_REQUIRES@
+Cflags: -I${includedir} @XSIMD_PKGCONFIG_CFLAGS@