In the field of Multi-Agent Systems (MASs), methodologies and infrastructures have developed in the last years along two opposite paths: while Agent-Oriented methodologies have essentially undergone a top-down evolution, MAS infrastructures have mostly followed a bottom-up path, producing a conceptual gap between methodologies and the available agent infrastructures. This paper aims at defining a method for filling such a gap, based on Situational Method Engineering (SME) and SPEM (Software Process Engineering Meta-model).After highlighting the lack of sufficient research and understanding about the role of the infrastructures in the software engineering process, we show that infrastructures, like methodologies, have processes behind them, and propose a method based on the integration of the processes underpinning both methodologies and infrastructures. Then, we validate such an approach by showing how the process of the SODA methodology can be integrated with the process of the TuCSoN infrastructure using SME and SPEM.