Software architecture practice is highly complex. Softwarearchitects interact with business as well as technical aspectsof systems, often embedded in large and changingorganizations. We first make an argument that an appropriateresearch agenda for understanding, describing, andchanging architectural practice in this context is based onan action research agenda in which researchers use ethnographictechniques to understand practice and engages directlywith and in practice when proposing and designingnew practices. Secondly, we present an overview of an ongoingproject which applies action research techniques tounderstand and potentially change architectural practice infour Danish software companies.