In 1991 he conceived the idea of The Eden Alternative, a new approach to the care of frail elders. Facilities that adopt The Eden Alternative bring decision-making in line with the needs of the Elders, rather than bureaucratic priorities. Once this cultural change has been accomplished they will be able to successfully introduce large numbers of companion animals, indoor plants, gardens and children. Dr. Thomas also pioneered the next phase in care for frail elders with the Green House Project.