diff --git a/CMakeLists.txt b/CMakeLists.txt
index b345c77a56..8d584c59c8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -26,17 +26,17 @@ set(NLOHMANN_JSON_CONFIG_INSTALL_DIR        "lib/cmake/${PROJECT_NAME}"
   CACHE INTERNAL "")
 set(NLOHMANN_JSON_INCLUDE_INSTALL_DIR       "include")
 set(NLOHMANN_JSON_TARGETS_EXPORT_NAME       "${PROJECT_NAME}Targets")
-set(NLOHMANN_JSON_CMAKE_CONFIG_TEMPLATE     "cmake/config.cmake.in")
+set(NLOHMANN_JSON_CMAKE_CONFIG_TEMPLATE    "${CMAKE_CURRENT_LIST_DIR}/cmake/config.cmake.in")
 set(NLOHMANN_JSON_CMAKE_CONFIG_DIR          "${CMAKE_CURRENT_BINARY_DIR}")
 set(NLOHMANN_JSON_CMAKE_VERSION_CONFIG_FILE "${NLOHMANN_JSON_CMAKE_CONFIG_DIR}/${PROJECT_NAME}ConfigVersion.cmake")
 set(NLOHMANN_JSON_CMAKE_PROJECT_CONFIG_FILE "${NLOHMANN_JSON_CMAKE_CONFIG_DIR}/${PROJECT_NAME}Config.cmake")
 set(NLOHMANN_JSON_CMAKE_PROJECT_TARGETS_FILE "${NLOHMANN_JSON_CMAKE_CONFIG_DIR}/${PROJECT_NAME}Targets.cmake")
 
 if (JSON_MultipleHeaders)
-    set(NLOHMANN_JSON_INCLUDE_BUILD_DIR "${PROJECT_SOURCE_DIR}/include/")
+    set(NLOHMANN_JSON_INCLUDE_BUILD_DIR "${CMAKE_CURRENT_LIST_DIR}/include/")
     message(STATUS "Using the multi-header code from ${NLOHMANN_JSON_INCLUDE_BUILD_DIR}")
 else()
-    set(NLOHMANN_JSON_INCLUDE_BUILD_DIR "${PROJECT_SOURCE_DIR}/single_include/")
+    set(NLOHMANN_JSON_INCLUDE_BUILD_DIR "${CMAKE_CURRENT_LIST_DIR}/single_include/")
     message(STATUS "Using the single-header code from ${NLOHMANN_JSON_INCLUDE_BUILD_DIR}")
 endif()
 
@@ -58,12 +58,12 @@ target_include_directories(
 ## add debug view definition file for msvc (natvis)
 if (MSVC)
     set(NLOHMANN_ADD_NATVIS TRUE)
-    set(NLOHMANN_NATVIS_FILE "nlohmann_json.natvis")
+    set(NLOHMANN_NATVIS_FILE "${CMAKE_CURRENT_LIST_DIR}/nlohmann_json.natvis")
     target_sources(
         ${NLOHMANN_JSON_TARGET_NAME} 
         INTERFACE 
             $<INSTALL_INTERFACE:${NLOHMANN_NATVIS_FILE}>
-            $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/${NLOHMANN_NATVIS_FILE}>  
+            $<BUILD_INTERFACE:${NLOHMANN_NATVIS_FILE}>
     )
 endif()
 
@@ -75,12 +75,13 @@ include(CTest) #adds option BUILD_TESTING (default ON)
 
 if(BUILD_TESTING AND JSON_BuildTests)
     enable_testing()
-    add_subdirectory(test)
+    add_subdirectory("${CMAKE_CURRENT_LIST_DIR}/test" "${CMAKE_BINARY_DIR}/json-tests")
 endif()
 
 ##
 ## INSTALL
-## install header files, generate and install cmake config files for find_package()
+## install header files, generate and install cmake config files for find_package();
+## but only if Nlohmann JSON is the main project being built.
 ##
 include(CMakePackageConfigHelpers)
 write_basic_package_version_file(
@@ -91,33 +92,35 @@ configure_package_config_file(
     ${NLOHMANN_JSON_CMAKE_PROJECT_CONFIG_FILE}
     INSTALL_DESTINATION ${NLOHMANN_JSON_CONFIG_INSTALL_DIR}
 )
-
-install(
-    DIRECTORY ${NLOHMANN_JSON_INCLUDE_BUILD_DIR}
-    DESTINATION ${NLOHMANN_JSON_INCLUDE_INSTALL_DIR}
-)
-install(
-    FILES ${NLOHMANN_JSON_CMAKE_PROJECT_CONFIG_FILE} ${NLOHMANN_JSON_CMAKE_VERSION_CONFIG_FILE}
-    DESTINATION ${NLOHMANN_JSON_CONFIG_INSTALL_DIR}
-)
-if (NLOHMANN_ADD_NATVIS)
-    install(
-        FILES ${NLOHMANN_NATVIS_FILE}
-        DESTINATION .
-)
-endif()
 export(
     TARGETS ${NLOHMANN_JSON_TARGET_NAME}
     NAMESPACE ${PROJECT_NAME}::
     FILE ${NLOHMANN_JSON_CMAKE_PROJECT_TARGETS_FILE}
 )
-install(
-    TARGETS ${NLOHMANN_JSON_TARGET_NAME}
-    EXPORT ${NLOHMANN_JSON_TARGETS_EXPORT_NAME}
-    INCLUDES DESTINATION ${NLOHMANN_JSON_INCLUDE_INSTALL_DIR}
-)
-install(
-    EXPORT ${NLOHMANN_JSON_TARGETS_EXPORT_NAME}
-    NAMESPACE ${PROJECT_NAME}::
-    DESTINATION ${NLOHMANN_JSON_CONFIG_INSTALL_DIR}
-)
+
+if($PROJECT_SOURCE_DIR STREQUAL $CMAKE_CURRENT_LIST_DIR)
+    install(
+        DIRECTORY ${NLOHMANN_JSON_INCLUDE_BUILD_DIR}
+        DESTINATION ${NLOHMANN_JSON_INCLUDE_INSTALL_DIR}
+    )
+    install(
+        FILES ${NLOHMANN_JSON_CMAKE_PROJECT_CONFIG_FILE} ${NLOHMANN_JSON_CMAKE_VERSION_CONFIG_FILE}
+        DESTINATION ${NLOHMANN_JSON_CONFIG_INSTALL_DIR}
+    )
+    if (NLOHMANN_ADD_NATVIS)
+        install(
+            FILES ${NLOHMANN_NATVIS_FILE}
+            DESTINATION .
+    )
+    endif()
+    install(
+        TARGETS ${NLOHMANN_JSON_TARGET_NAME}
+        EXPORT ${NLOHMANN_JSON_TARGETS_EXPORT_NAME}
+        INCLUDES DESTINATION ${NLOHMANN_JSON_INCLUDE_INSTALL_DIR}
+    )
+    install(
+        EXPORT ${NLOHMANN_JSON_TARGETS_EXPORT_NAME}
+        NAMESPACE ${PROJECT_NAME}::
+        DESTINATION ${NLOHMANN_JSON_CONFIG_INSTALL_DIR}
+    )
+endif()
\ No newline at end of file