In the last two decades, the civilian dimension has become an essential aspect of peace operations. In 2010, the un had deployed 20 000 civilians in peace operations, while the eu and the osce had sent 2 000 and 3 000 civilians. This dimension also is one of the bases of the African Standby Force of the African Union. This article gives a preliminary overview of the reinforcement of civilian capacities in peace operations, a topic that hasn’t been broadly covered by the literature, except through the broad scope of peacebuilding. This article addresses the concept of the civilian dimension though the evolution of peacekeeping, then analyses its slow and laborious emergence. Finally, it identifies some of the main operational challenges of its development.