The rate of addiction among adults in the opium-growing areas of South East Asia and the Middle EAst varies between 3 per cent and 10 per cent. Supply-reduction efforts alone have rarely been successful and programmes aimed concurrently to reduce demand are now being initiated. Primary health care is considered a prerequisite for the success of demand-reduction programmes and includes the training of primary health care workers to assist in prevention programmes as well as in the treatment and rehabilitation of addicted persons. This supply-demand-reduction approach will require careful evaluation of its effectiveness.