As we age, we experience normal declines in vision, hearing, cognition, and movement. We also accumulate chronic conditions such as arthritis, heart and circulatory disorders, glaucoma, and tinnitus. Quality of life and independence are impacted by disabilities, and our health and caregiver systems will be increasingly stressed as the numbers increase. Hence, there is a significant need today to innovate cost-effective ways to help elders maintain their independence, and at the same time, reduce caregiver burden. The impressive wireless and portable technologies we have today and the emerging mobile computing paradigm offer a unique and real opportunity for us to innovate pervasive applications and environments designed to support the elderly. Such environments will enable cost-effective self-care and will maintain a higher quality of life and independence for our oldest population. In this chapter, we define assistive environments for the elderly, and we follow a scenario-based approach to illustrate the benefits of these environments to the elders. We then present a specific assistive environment, which we prototyped, and which we call the University of Florida Rehabilitation Engineering Research Center (RERC) Smart House. We present our reference middleware architecture and several applications that we built in that experimental house. Finally, we review research on smart environments for elders with disabilities, and elder health care applications and practices. © 2005 by John Wiley & Sons, Inc. All rights reserved.