Team composition affects the creativity of teams in design tasks. Existing research presents mixed results on the impact of team composition on creativity. We conducted an experiment to investigate the effect of three different team categories on design creativity: designers, designers and non-designers (mixed teams), and non-designers. 18 volunteer dyads completed a short design task by generating solution ideas. Three expert judges scored the ideas for originality, usefulness, and compliance with requirements. The judges also assigned independent subjective creativity scores. Fluency and rareness were also calculated. Findings indicate that mixed dyadic teams score highest in almost all variables, thereby suggesting that design is no different than other domains, thus adding to the literature that favors diverse teams for increased creativity.