In this article, the author argues that there is a systematic tendency of some actors operating in the field of peace and security to resist cooperation and disregard the importance of coordination. Their inability to see the value of interdependence resulting from frailty and short-sightedness leads to unhealthy relationships and unsatisfactory outcomes. Through an analysis of the peacebuilding field, the article reflects on the central role played by cooperation and coordination. Focusing on the case of Libya, the author examines some cooperation and coordination strategies pursued by the United Nations support mission and highlights promising results that have recently been achieved thanks to its dedication and determination. The conclusion is that it is worth investing in cooperation and coordination in the peacebuilding field; however, as it stands today, fundamental changes are needed in the way cooperation is carried out while it remains desirable to reconsider how coordination is pursued.