A wealth of research has suggested that emotions play a significant role in the creative problem solving process, but less work has focused on investigating the role of emotions in the design process. This is surprising given that creative problem solving lies at the heart of the design processes. In an exploratory study we interviewed 9 expert designers about their emotions during the design process. The content analysis allowed us to identify the various types of emotions relevant in the design process and to extend Wallas’ model of creative problem solving with emotional components for each of its stages. In addition, we identified two important roles of emotions in design and several ways in which expert designers regulate their emotions. We discussed the theoretical and practical applications of our work.