As markets grow in complexity and scale, more co-operative approaches on remedies can improve enforcement effectiveness and prevent inconsistent outcomes. This paper explores the design of remedies in competition enforcement, with a particular focus on the value of co-operation between competition authorities and other public and private stakeholders. It introduces the concept of remedies, outlines key definitions and principles, and explores how collaboration can enhance remedies effectiveness. It also examines the architecture of co-operation, as well as the relevant challenges.