In most parts of the country today it is often difficult or impossible to fill consultant vacancies in mental handicap. According to the DHSS there were 146 consultants in mental handicap in post in 1978 compared with 102 in 1968, an overall growth of 43 per cent, compared with 34.7 per cent in general psychiatry. Nevertheless nearly one quarter of posts were vacant on 30 September 1978. The number of new consultants in mental handicap required to replace losses from death and retirement is about 6 to 10 per year. If an expansion of 10 is to be achieved some 16 to 20 fully trained senior registrars will be required each year. For this 60 senior registrar posts will be needed, assuming that senior registrars have three to four years training. At the end of September 1978 there were 34 established senior registrar posts of which 9 were vacant.