Summary: During the summer and autumn of 1964 the British Radio Equipment Manufacturers Association (B.R.E.M.A.) carried out extensive tests of N.T.S.C. colour television receivers, to assess their performance under typical domestic operating conditions. This paper describes the organization of these tests and records the results obtained. It was found, somewhat unexpectedly, that the viewers found the (u.h.f.) tuning controls easy to use and this may be regarded as very satisfactory since the quality of the picture obtained was good.