Integration with Other Applications > Windchill Workgroup Manager Documentation > NX > Advanced Techniques > Managing NX Part Families > Rules for Opening a Part Family
  
Rules for Opening a Part Family
Consider these rules for using Open or Open from Windchill:
You can open each member of the part family individually if it is managed in Windchill.
If you select a top-level generic to open and the generic is not in the workspace, then Windchill Workgroup Manager adds only the generic to the workspace.
If you select an instance, and the instance is not in the workspace, then the instance and its Part Family generic must be added to the workspace.