The purpose of this paper is to provide a methodology for profiling and binary encoding MPEG REL for developing efficient and yet interoperable embedded DRM systems. This paper begins with a brief introduction of the MPEG REL, and a discussion of the concepts and general principles of profiles of any XML-based specification and their binary encoding. Then, this paper presents a case study of creating an example profile and binary encoding of the MPEG REL for the mobile domain. The case study covers collecting and analyzing requirements for current mobile DRM systems, presenting the profile to satisfy these requirements, and demonstrating how binary encoding of the profile can be carried out in a systematic way.