Recent bio-demographic change in Bulgaria is analysed in conjunction with socio-economic trends. The exceptionally serious problem of the "ageing population" is outlined, and its main socio-economic consequences are discussed. The main reason for the population aging is the low fertility rate and the large number of emigrants, especially during the last decade. For the population in Bulgaria to grow at all, policies need to be adopted to increase the fertility rate, lower the emigration rate, and provide incentives for those who have already left the country to return. Furthermore, social policies are needed to support the family, in order to encourage fertility and improve the social and health status of population. The socio-economic crisis that began in the 1990s must be overcome before the standard of living can increase.