Product Line Engineering has a widespread use in industry now. Therefore there is a high need for customizable, adaptable, and also for mature methods. Scoping is an integral part of Product Line Engineering. In this phase we determine where to reuse and what to reuse, establishing the basis for all technical, managerial, and investment decisions in the product line to come. In this tutorial we will give an introduction on how to analyze an environment with the purpose of planning a product line and its future evolution.