The performances of a group of unilateral above-knee amputees using prostheses with quadrilateral sockets of the ischial-bearing type were evaluated economically by subjecting them to a battery of tests representing the commonest activities of daily living and working. The Test Group also included an isolated case of an above-knee amputee wearing a prosthesis with a ’ plug-fit ’ type socket. During each test, the oxygen consumption, pulmonary ventilation, energy expenditure and peak heart rate were measured for each subject. To assess the degree of normality restored, performances of the Test Group subjects were compared with those of a Control Group consisting of sixteen normal, healthy, adult males of sedentary habits. Although the weight-bearing ability of the above-knee prosthetic rehabilitees was found to have been fully restored, restoration of the other major quality of the lower extremity, namely freedom of movement, was observed to depend largely on the regularity and length of use of the prosthesis. It was confirmed that with a regular and long period of use, a high degree of amputee-prosthesis integration is possible, even with a not over-sophisticated and reasonably acceptable mode of construction. The evaluation brought out the shortcomings of some of the Test Group subjects. Nevertheless, it established that such above-knee prosthetic rehabilitees should not have any difficulty in leading a normal domestic life and also in carrying out the tasks pertaining to industrial occupations of up to moderately heavy grade. © 1974 Taylor & Francis Group, LLC.