diff --git a/GeoModelJSONParser/CMakeLists.txt b/GeoModelJSONParser/CMakeLists.txt
index 03f7a90fbcab87520a3540695df10b905b087ac1..595d0ca3f105b9e0c837fba108bbec402a3a4117 100644
--- a/GeoModelJSONParser/CMakeLists.txt
+++ b/GeoModelJSONParser/CMakeLists.txt
@@ -6,7 +6,12 @@ file( GLOB HEADERS GeoModelJSONParser/*.h )
 
 # Create the library.
 add_library( GeoModelJSONParser SHARED ${HEADERS} ${SOURCES} )
-target_link_libraries( GeoModelJSONParser PUBLIC nlohmann_json::nlohmann_json )
+if (nlohmann_json_FOUND)
+  # we link to nlohmann_json only  if we use a version of nlohmann_json installed through CMake;
+  # this is not needed if the single-header library is installed in a regular
+  # system include folder (e.g., '/usr/local/include')
+  target_link_libraries( GeoModelJSONParser PUBLIC nlohmann_json::nlohmann_json )
+endif()
 target_include_directories( GeoModelJSONParser PUBLIC
    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
    $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}> )
diff --git a/cmake/SetupJSON.cmake b/cmake/SetupJSON.cmake
index 3bd3539dc2f18fc31bf5f1ade670f004c6f8d3b1..6e77d8a70fa6b5c51770ab4117dddd1539217b1c 100644
--- a/cmake/SetupJSON.cmake
+++ b/cmake/SetupJSON.cmake
@@ -13,7 +13,7 @@ option( GEOMODEL_USE_BUILTIN_JSON
 if( GEOMODEL_USE_BUILTIN_JSON )
 
    # Tell the user what's happening.
-   message( STATUS "Building nlohmann_json as part of the project" )
+   message( STATUS "'GEOMODEL_USE_BUILTIN_JSON' was set to 'true' ==> Building nlohmann_json as part of the project" )
 
    # The include directory and library that will be produced.
    set( nlohmann_json_INCLUDE_DIR
@@ -50,6 +50,9 @@ if( GEOMODEL_USE_BUILTIN_JSON )
 else()
 
    # Just find an existing installation of nlohmann_json.
-   find_package( nlohmann_json )
+   find_package( nlohmann_json QUIET)
+   if( NOT nlohmann_json_FOUND )
+     message(STATUS "WARNING! 'nlohmann_json' was not found by CMake!! However, if you installed this single-header library in a standard system include dir (e.g., '/usr/local/include'), I will be able to use it.")
+   endif()
 
 endif()