The transition to agile software development changes the decision-making power in organizations. This study aims to provide researchers and practitioners with empirical insights into how the participation in decision-making by enterprise, solution and system architects evolves due to this transition. For this purpose, a case study was conducted to examine the participation of and challenges for architects in decision-making in agile projects. A mixed-method research approach was used comprising observations, conversations, interviews, literature study and a survey. We found that 101 decision types are used prior to and in agile iterations, in which architects and stakeholders collaborate to make these decisions. The projection of these types of decisions over 25 different actors in the case study organization demonstrates that decision-making is a group effort in which solution and system architects are highly involved. Architecture and agility can indeed co-exist. Another finding of this case study is that stakeholders in agile teams perceive less architecture involvement in decision-making and expect less design decisions up front. Architects are challenged to become team players, to make design decisions only when they are necessary, and finally, to document, communicate, and share design decisions more effectively.