Reports about application of the Extreme Programming - XP method, have evidenced scalability problems in both, the team size and the problem complexity. When the problem is more complex and the team size is bigger, organization of team, project and product became to have more relevance. Architecture practices deal with these concerns, so these are key elements for achieving any scalable XP extension. In this paper we propose XA (XP with Architecture), an XP extension including adapted architecture practices from architecture centered approaches. Furthermore, the paper presents a study case where XA is applied in a project in an academic context.