Learning is considered to be an essential component of organizational effectiveness in all sectors—private, public and non-governmental. All NGOs aspire to be ‘learning organizations’, yet few have reflected systematically on the success in this regard. This article summarizes the experience to date of international NGOs that have prioritized learning as an objective, drawing out areas of both success and failure, and reflecting on whether there are any features that distinguish learning in NGOs from learning in other types of organization. A simple typology and set of tests of NGO-learning are presented, along with a series of challenges for the future.