The problem of composing services to deliver integrated business solutions has been widely studied in the last years. Besides addressing functional requirements, services compositions should also provide agreed service levels. The authors' goal is to support model-based analysis of service compositions, with a focus on the assessment of non-functional quality attributes, namely performance and reliability. They propose a model-driven approach, which automatically selects the set of available services, transforms a design model of service composition into an analysis model, which then feeds a probabilistic model checker for quality prediction. To bring this approach to fruition, they developed a prototype tool and they show the results which can be achieved with a simple example.