This research aims to improve the work effectiveness of people with physical disabilities in department stores, retail and wholesale companies in Bangkok. It focuses on the environment and facilities needed by people with three types of disabilities, visual impairment, hearing impairment, and wheelchair users. A mixed research method was used (questionnaires, interviews, and observations). The results were applied to a design process based on the needs of people with physical disabilities and addressed solving their work problems, increasing their work effectiveness, and bringing the results of the design to a group discussion. The group was made up of 15 experts who were supervisors, representatives of the people with each type of physical disability, instructors, and personnel from the university knowledgeable about universal design for people with disabilities. Architects and designers helped to brainstorm ideas and develop designs that led to production and product testing. Testing was conducted to compare pretest and posttest results using designed products to evaluate the work effectiveness of the people with physical disabilities using statistical analysis (paired t-tests). The results using developed products showed a higher average posttest score than pretest. This indicated a statistically higher work effectiveness (α =0.05) and supports the research hypothesis.