Abstract: The MPEG-21 standard defines a framework for the delivery and consumption of multimedia content. Within this framework the adaptation of content plays a vital role in order to support a variety of terminals and to overcome the limitations of the heterogeneous delivery networks. In most cases the multimedia content can be adapted by applying different adaptation operations that result in certain properties of the content. Therefore, an instance within the framework has to decide which adaptation operations have to be performed to achieve a satisfactory result. This process is known as adaptation decision taking and makes extensively use of metadata describing the possible adaptation operations, the usage environment of the consumer, and constraints concerning the adaptation. Based on this metadata a mathematical optimization problem can be formulated and its solution yields the optimal parameters for the adaptation operations. However, this generic approach enables a very generic class of optimization problems that are difficult to solve. Furthermore, the metadata is represented in XML resulting in a very verbose and ineffcient encoding. In this thesis an architecture for an Adaptation Decision Taking Engine (ADTE) is introduced. The ADTE operates both on XML metadata and on metadata encoded with the Binary Format for Metadata (BiM) enabling an effcient metadata processing. Concerning the solving of the optimization problem three different algorithms, ranging from a simple generate and test approach to the sophisticated Mesh Adaptive Direct Search, were implemented and evaluated.