The article deals with structurally spatial aspects of populated centres in regions. From the point of urban planning, the main accent is put on the hierarchy of populated areas based on National or Republic significance, regional significance, significance of districts and centres of local significance. This hierarchical system is based on socio – economic interaction and also on differentiation and integration processes of everyday periodical and episodical services. As the most typical functions of populated centres could be mentioned administrative authority, communications and information, commerce and public catering, household services, cultural life, recreation, external traffic hubs and construction centre. The second aspect of spatial development of regions analyzed in the article deals with structurally spatial formation of populated centres. It is reasoned that differential zones must created when planning the structures of centres where the main service sectors of town and its bordering districts are divided, thus, creating architecturally spatial systems of populated areas in the united renewed Republic of Latvia, and harmonious composition of populated areas as well, which is considered to be one of the most important tasks in the field of regional territorial planning and urban construction.