This paper aims at analysing the interactions between inmates and between inmates and the penitentiary authorities, in a carceral situation, from a spatial point of view. It focuses especially on internal mobilities, in the Kondengui Central Prison, Yaounde. The Prison is overcrowded. It was built in 1968 for 1 000 inmates and now hosts 4 000 of them. This overcrowding acts upon the appropriation of space and the power structures within the prison, in a context where the prisoners are unevenly divided into the 13 districts of the Kondengui neighbourhood. There is a co-management of the prison based on a doublehierarchy : guards control inmates but delegate some of the work of surveillance to some inmates. Following agift/counter-gift systemwith guards, some inmates have certain privileges in jail. To have the control of some places and doorsteps means money, status and power. Other prisoners can also corrupt the guards to have some local benefits. Their is no way one could make a binary opposition between the formal prison organization and the inmates’and guards’informal tactics and strategies. Informal and institutional practices create a specific power apparatus, to maintain order inside the prison. This paper therefore proposes a microgeography of the carceral space to understand the power relationships between guards and inmates, and between prisoners, in a context of confinement. Ann. Géo.,