To sustain the qualities of a software system during evolution, and to adapt the quality attributes as the requirements evolve, it is necessary to have a clear software architecture that is understood by all developers and to which all changes to the system adheres. This software architecture can be created beforehand, but must also be updated as the domain of the software, and hence the requirements on the software system evolve. Creating a software architecture for a system or part of a system so that the architecture fulfils the desired quality requirements is often hard. We propose a decision-support method to aid in the understanding of different architecture candidates for a software system. We propose a method that is adaptable with respect to both the set of potential architecture candidates and quality attributes relevant for the system's domain to help in this task. The method creates a support framework, using a multicriteria decision method, supporting comparison of different software architecture candidates for a specific software quality attribute and vice versa, and then uses this support framework to reach a consensus on the benefits and liabilities of the different software architecture candidates and to increase the confidence in the resulting architecture decision.