In this diploma thesis a model was presented for describing composite cloud applications and provisioning services in a way such that the provisioning can be handled automatically. An algorithm was presented that calculates a cost-optimal provisioning by transforming the problem of provisioning planning into a constraint optimization problem. In order to get information about available provisioning services, this algorithm has to issue requests to the provisioning service bus. A corresponding algorithm was explained that is able to match requested deployment trees to those offered by some provisioning service – how this algorithm could be implemented by a provisioning service bus using WS-Policy was shown, too.