The evaluation of disease management programmes is necessary and has been made obligatory in Germany by the Fifth Book of Social Code. So far there has been extensive ambiguity as regards the precise definition of suitable strategies for the evaluation. Considering the scientific evaluation of the diabetes contract in North-Rhine current deficits of the evaluation of already existing programmes for chronically ill patients are exemplarily described. On the basis of international experience reasonable demands are discussed that ought to be accomplished when evaluating the effectiveness and benefit of the programmes. Taking the British Medical Research Council as an example, a four-step model will be suggested as a loophole in the methodological dilemma of varying suitable study designs, which allows for the adequate evaluation of even complex interventions.