Design, Monitoring and Evaluation (DM&E) of peace & conflict and security & justice programmes pose numerous challenges. Best practises, though long established and indeed accepted at the institutional and field-wide levels, are often lacking or missing altogether.1 In situations of conflict and fragility, the need for best practises is further accentuated with the very real possibility of causing harm or exacerbating conflict. The integration of best practises throughout the programme cycle is even more challenging in situations of conflict and fragility despite the heightened need for such practises. This guidance therefore seeks to outline best practises in the design, monitoring and evaluation of programmes spanning the width of peace & conflict, and security & justice, while highlighting the unique challenges, opportunities and lessons learned of the best practices in situations of conflict and fragility (also referred to in this document as fragile and conflict affected states, FCAS).