diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1c286358..da9bd233 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -349,6 +349,12 @@ else()
     set (OPENSSL_LIBS ${lib_ssl} ${lib_crypto})
 endif()
 
+
+# Check we have the *required* Qt5 libs.
+find_package(Qt5Core REQUIRED)
+find_package(Qt5Network REQUIRED)
+find_package(Qt5Widgets REQUIRED)
+
 #
 # Configure_file... but for directories, recursively.
 #