It may be something of a paradox, but the demise of central planning has been parallelled by a surge of work on urbanisation in socialist countries. This paper focuses on the topic of suburbanisation, taking Estonia as a case. To understand more neatly the processes at work, a conceptual distinction between the terms suburban growth, suburbanisation in a narrow (statistical) and wide (including mechanisms of population change) sense is proposed. As part of the wider definition, the following characteristics of suburbanisation in Western countries are brought out: the inner decentralisation of population within agglomerations for environmental reasons, the spread of low-density, detached housing together with blurring of borders between urban and rural areas, and the relation to people's life-course. These form a baseline for comparative research which reveals both similarities and differences in suburban population developments in Estonia.