Multiple Criteria Decision Aid (MCDA) algorithms help making the right decision. However, choosing and using an MCDA algorithm very often represents only a short and precise event of a much longer decision aid process. Moreover, this process involves multiple conflicting criteria and various stakeholders. In this work, we actually formalize a business process model of the MCDA process. Such a business process is a set of discrete activity steps, with associated computer and/or human operations, and rules governing the progression of the process through the various activity steps. The activities are supported/implemented by an Information System. This Information System consists, in this study, in (web-)services (via Service Oriented Architecture, SOA) which expose MCDA algorithms. We are also studying the alignment (i.e. the extent of correspondence) of models of this Information System (i.e. the MCDA services) with the MCDA process model. This alignment results, for each activity of the MCDA process, in an inventory of the services which fulfill it partially or totally. The analysis of this alignment improves the relevance and completeness of the definition of the MCDA services which realize the process, thus contributing towards guiding/automating the process.