Handset development is progressing on two parallel lines. Today's phones are running various applications such as commerce, games, and data retrieval. This requires an open platform for application execution. On the other hand there is an increased need for DRM. DRM by nature requires that data is blocked by the device. Inherently, completely open platforms cannot provide means for such data blockage. There is a way to bridge these two contradicting requirements, which is by means of a secure and isolated subsystem that is integrated with the operating system. This presentation draws the lines for the implementation of such a system - a system that adopts the smallest possible subset of secure environment components to provide an environment that allows arbitrary applications to run side by side with a DRM (or other secure) application.