Research is proceeded intensively on the hybrid electric vehicle (HEV) sector to find new concepts for reducing fuel consumption and emissions. In the same time comfort and fun-to-drive are to be improved. In spite of these advanced technical requirements the costs of a hybrid electric vehicle should be minimized. Technical effort to reduce fuel consumption is always associated with rising costs. Acceleration cannot be essentially improved without rising fuel consumption. The hybrid powertrain is a complex system that does not allow focusing on single components. The complete system has to be considered for any analysis. An evaluation method is presented that is based on various algorithms for solving multidimensional decision problems. It operates with criteria of the mentioned categories and merges them with the weighting algorithm AHP (analytic hierarchy process). To avoid complex modelling for each topology the evaluation is based on functional attributes. The evaluation method supports the detection process of the appropriate hybrid powertrain architecture. The next step is to clarify the way of implementation of the hybrid system. From the point of view of an automotive component supplier a modular architecture of hybrid powertrain is preferred. Considering a parallel hybrid vehicle for instance it can be implemented as an integrated hybrid module. Such a module extends the conventional propulsion to a hybrid powertrain by installing an electric drive between engine and transmission. The electric drive is combined with a clutch which allows disconnecting the engine from the powertrain. For the layout of that subsystem a detailed modelling of clutch and electric drive is necessary to analyse their characteristics. In addition the electric drive model is supposed to be flexible enough to vary its parameters continuously for optimization purposes of the vehicle. A hybrid module modelling with these considerations is presented in this paper