Determining the success of development projects and programmes is often portrayed and understood as a question of measurable impact and effectiveness. More often than not however, success is a negotiated truth, socially constructed between the involved stakeholders that does not require measurable results of impact, and may very well hold the opposite circumstances. By examining the Intergovernmental Authority on Development in the Horn of Africa, the article investigates one such case of development project success despite substantial impact on the ground. Success in development cooperation, the article argues, is not a matter of attaining impact, but is rather constructed in the overlapping space between representation and interpretation of events, actions and discourses, made and sustained socially between recipient and donor.