A socialist state, socialist republic, or socialist country, sometimes referred to as a workers' state or workers' republic, is a sovereign state constitutionally dedicated to the establishment of socialism. The term communist state is often used synonymously in the West, specifically when referring to one-party socialist states governed by Marxist–Leninist communist parties, despite these countries being officially socialist states in the process of building socialism and progressing toward a communist society. These countries never describe themselves as communist nor as having implemented a communist society. Additionally, a number of countries that are multi-party capitalist states make references to socialism in their constitutions, in most cases alluding to the building of a socialist society, naming socialism, claiming to be a socialist state, or including the term people's republic or socialist republic in their country's full name, although this does not necessarily reflect the structure and development paths of these countries' political and economic systems. Currently, these countries include Algeria, Bangladesh, Guyana, India, Nepal, Nicaragua, Sri Lanka and Tanzania.

Socialism is an economic and political philosophy encompassing diverse economic and social systems characterised by social ownership of the means of production, as opposed to private ownership. It describes the economic, political, and social theories and movements associated with the implementation of such systems. Social ownership can take various forms, including public, community, collective, cooperative, or employee. Traditionally, socialism is on the left wing of the political spectrum. Types of socialism vary based on the role of markets and planning in resource allocation, and the structure of management in organizations.