They were given extensive powers, and manage economic development, transportation, or environmental protection issues at the regional level, thus coordinating the actions of the communes below them.

The commune of Dakar, whose population approached 1 million inhabitants, was deemed too large and too populated to be properly managed by a central municipality, and so on August 30, 1996 Dakar was divided into 19 communes d'arrondissement.

Dakar Department includes the commune d'arrondissement of Dakar-Plateau (34,626 inhabitants), in the arrondissement of Plateau/Gorée, is the historical heart of the city, and most ministries and public administrations are located there.

The densest and most populous commune d'arrondissement is Médina (136,697 inhabitants), in the arrondissement of Plateau/Gorée.

The smallest one is the commune d'arrondissement of Île de Gorée (1,034 inhabitants), in the arrondissement of Plateau/Gorée.