CO-DESIGN AND USER-CENTERED PRODUCT DEVELOPMENT: ENGAGING SOCIALLY VULNERABLE GROUPS IN THE DESIGN PROCESS

User-centered design has long held that products are improved when designed around the needs of those who will use them, while co-design extends this commitment by inviting users to act as creative partners rather than research subjects. The shift carries particular weight for socially vulnerable groups, including older adults, disabled people, children and migrant or low-income communities, whose needs are frequently under-represented in mainstream product development and who may face additional barriers to participation itself. This paper examines how co-design and user-centered product development can be adapted to meaningfully include such groups. Through a conceptual and integrative review of literature in participatory design, human–computer interaction, inclusive design and research ethics, it develops a five-part framework covering recruitment and representation, the adaptation of participatory techniques, power-sharing and consent, the facilitator's relational role, and the evaluation of participatory impact. The analysis shows that including vulnerable groups in co-design is not a simple extension of standard methods but requires deliberate redesign of the participatory process itself, and that failure to do so risks tokenistic involvement that produces the appearance, but not the substance, of participation. The paper closes with implications for practice and five propositions for empirical testing.