The HOS and PSPS were introduced by the HKHA in 1978 and 1979 respectively, to assist low and middle income households to purchase homes at discounted prices.

• 房屋委员会在一九七八、一九七九年先后推出居屋计划及私人机构参建居屋计划，以折让价格出售居屋，协助中等及低入息家庭置业。