This article was motivated by Brazil War College Seminars carried out in order to provide subsidies for the National Defense Policy and Strategy (published in 2008) update. It has the scope to perform a defendant on the Brazilian participation in peacekeeping operations conducted by international organizations and to assess the relationship between the Brazilian diplomacy and defense segment promoted by such activities. Then, it presents general concepts on peace operations under the auspices of international organizations, provides an overview of the Brazilian participation in such operations, and evaluates the relationship between the segments of diplomacy and defense in this context. At conclusion, it shows as advantageous the Brazilian presence in this type of activity, for diplomats or soldiers. Besides, it exposes suggestions for improvement of this process.