With consortia and inter-agency collaboration increasingly a feature of the humanitarian landscape, the ECB Project took a day to reflect on the last 5 years of implementation of this innovative and unique collaboration with various stakeholders of the humanitarian system. While not an exhaustive portfolio of learning, the day focused on some of the approaches taken to build and measure capacity, broad lessons learned from working in a consortium and two case studies on collaborative publishing and collaborative fundraising. This paper summarises the day’s discussions.