diff --git a/README.md b/README.md
index 8455eba..df938a7 100644
--- a/README.md
+++ b/README.md
@@ -29,12 +29,16 @@ add_executable(my-parser my-parser.cpp)
 target_link_libraries(cpm-test LarsParser)
 ```
 
+# Update packages
+
+To update packages, run cmake with the additional option `-DCPM_RESET=ON`. To keep the project working offline after the update, set `-DCPM_RESET=OFF` afterwards.
+
 # Installation
 
 To add CPM to your current project, copy the scripts in the `cmake` directory into you current project project. The command below will perform this automatically.
 
 ```bash
-wget -qO- https://github.com/TheLartians/CPM/releases/download/v0.2/cmake.zip | bsdtar -xvf-
+wget -qO- https://github.com/TheLartians/CPM/releases/download/v0.3/cmake.zip | bsdtar -xvf-
 ```
 
 # Limitations
diff --git a/cmake/CPM.cmake b/cmake/CPM.cmake
index 38e2342..7a551b0 100644
--- a/cmake/CPM.cmake
+++ b/cmake/CPM.cmake
@@ -2,10 +2,13 @@ set(_CPM_Dir "${CMAKE_CURRENT_LIST_DIR}")
 
 include(CMakeParseArguments)
 include(${_CPM_Dir}/DownloadProject.cmake)
-
-function(CPMHasPackage) 
   
-endfunction()
+option(CPM_RESET "reset CPM" OFF)
+
+if(${CPM_RESET})
+  message(STATUS "CPM: resetting packages")
+  set(CPM_PACKAGES "" CACHE INTERNAL "CPM Packages")
+endif()
 
 function(CPMAddPackage)
   set(options QUIET)
@@ -16,6 +19,7 @@ function(CPMAddPackage)
     VERSION
     GIT_TAG
     BINARY_DIR
+    UPDATE_DISCONNECTED
   )
 
   set(multiValueArgs "")
@@ -30,6 +34,15 @@ function(CPMAddPackage)
     set(CPM_ARGS_BINARY_DIR ${CMAKE_BINARY_DIR}/CPM-projects/${CPM_ARGS_NAME})
   endif()
 
+  if (NOT CPM_ARGS_UPDATE_DISCONNECTED)
+    if (${CPM_RESET})
+      set(CPM_ARGS_UPDATE_DISCONNECTED OFF)
+    else()
+      set(CPM_ARGS_UPDATE_DISCONNECTED ON)
+    endif()
+  endif()
+
+
   if (NOT CPM_PROJECT_DIR)
     set(CPM_PROJECT_DIR "${CPM_ARGS_BINARY_DIR}")
   endif()
diff --git a/cmake/CPMProject.CMakeLists.cmake.in b/cmake/CPMProject.CMakeLists.cmake.in
index 3bf475f..5f413c7 100644
--- a/cmake/CPMProject.CMakeLists.cmake.in
+++ b/cmake/CPMProject.CMakeLists.cmake.in
@@ -17,7 +17,7 @@ else()
     PROJ @CPM_ARGS_NAME@
     GIT_REPOSITORY @CPM_ARGS_GIT_REPOSITORY@
     GIT_TAG @CPM_ARGS_GIT_TAG@
-    UPDATE_DISCONNECTED 1
+    UPDATE_DISCONNECTED @CPM_ARGS_UPDATE_DISCONNECTED@
     GIT_SHALLOW 1
     PREFIX @CPM_ARGS_BINARY_DIR@/dl
     QUIET
diff --git a/tests/complex/CMakeLists.txt b/tests/complex/CMakeLists.txt
index de9ce3b..8454572 100644
--- a/tests/complex/CMakeLists.txt
+++ b/tests/complex/CMakeLists.txt
@@ -7,7 +7,7 @@ include(${CMAKE_CURRENT_SOURCE_DIR}/../../cmake/CPM.cmake)
 CPMAddPackage(
   NAME LHC
   GIT_REPOSITORY https://github.com/TheLartians/LHC.git
-  VERSION 0.3
+  VERSION 0.4
 )
 
 CPMAddPackage(