The human-computer interaction community is an umbrella for many disciplines. Conflicts occur from time to time, in particular between scientists and designers. This article compares the quality criteria used in design with those used in science, in order to gain insight into what design can contribute to the development of science. From the scientific perspective, the weakest point of design knowledge is its limited generalizability. Keywords Design, science, quality, criteria ACM Classification Keywords H5.0. Information interfaces and presentation (e.g., HCI): General.