Ever more firms are adopting codesign, which seeks to involve users in the process of innovation. The participation of user groups with specific needs in codesign could be helpful for delimiting these needs, taking them into account and moving toward a \u201cuniversal\u201d product design. However few approaches mix universal design and codesign; and the reciprocal effects of these two approaches have seldom been studied. In the three cases of codesign with disabled persons reported herein, user participation opened onto a global approach toward universal design that took into account all of a product\u2019s aspects and related uses. Specific characteristics of codesign with users who are disabled persons are pointed out that are related to the posture and beliefs of designers and of users. Recommendations are formulated for designers; and perspectives for further research, suggested.<\/p>\n