Belgian development cooperation is undergoing multiple reforms towards more integrated actions intending to improve the effectiveness of its interventions. In line with international debates and engagements, more coherent approaches are promoted. They include all different channels and actors and involve those best fitted to reach the objectives of Belgian foreign policy. In this context, the research group ‘Governance for development’ was asked by DGD to study two particular aspects: i) the trend towards a Comprehensive Approach (CA) that optimizes cooperation between actors, primarily the different federal departments, engaged in Belgian foreign action at large; ii) the implementation of an integrated country policy (or ICP) for development that optimizes collaborations between all actors of Belgian development cooperation around a country intervention strategy. This paper addresses the issue of the Comprehensive approach. In the words of the ACROPOLIS call for proposal, what was then called the 3D-LO (Development, Diplomacy, Defence – Law and Order) approach “also contributes to a coherent strategy at the national level, a unity of purpose in which every instrument of our foreign policy plays its part while staying in line with its own objectives (.). [It is] a tool to achieve better effectiveness of interventions addressing (human) security issues, and a more integrated approach in contexts of fragility, crisis or conflict. It is also a step towards a more integrated country-level approach encompassing all government and non-governmental stakeholders”. To succeed in such an ambitious reform, it is essential to clarify its context, meaning, and existing practices at Belgian level, as well as to look at international experiences from which lessons could be learned. In tackling all these aspects, this paper provides food for thought to Belgian stakeholders and wishes to lay the foundations for the debate and reforms carried out. The paper consists of two parts. The first part synthesizes Belgian and ...