Flanders (Dutch: Vlaanderen (help·info), French: Flandre) is the (political) community of the Flemings but also one of the institutions in Belgium, and a geographical region located in parts of present-day Belgium, France, and the Netherlands. Over the course of history, the geographical territory that was called "Flanders" has varied.

In contemporary Belgium, Flanders might be understood as the 'country of the Flemings'. This covers the north of Belgium Flemish Region and includes the Brussels Capital Region, the latter being shared with French speakers.

For the last few decades, with the legal establishment of the Flemish Community (Dutch: de Vlaamse Gemeenschap), the Flemings have their own political institutions. The parliament and government are the governing institutions of Flanders. There is also a geographical, political and administrative entity called the Flemish Region (Dutch: het Vlaams Gewest) but it has ceded all its competencies to the Flemish Community. Thus, the institutions of the Community govern both the Community and the Region. The capital city of Flanders is Brussels.

Previously, Flanders formed a county, the County of Flanders, which extended over:

The Belgian provinces of West Flanders and East Flanders
The French region French Flanders in the department Nord-Pas de Calais
The Dutch region Zeelandic Flanders (Zeeuws-Vlaanderen) in the province of Zeeland
Related to these geographical or political uses of the noun 'Flanders', and the adjective 'Flemish', they may also be used to describe several other distinct (but inter-connected) cultural, geographical, historical, linguistic or political items or entities.