The ability to assess the impact of humanitarian interventions is key both for priority-setting and for maximising the quality of projects. Humanitarian mine action (hma) is a young sector, where the application of impact assessment is still in its infancy. In this article we will briefly revisit the history of impact assessment in hma, before reviewing the strengths and weaknesses of three different impact-assessment approaches: 1) the Landmine Impact Survey; 2) economic analysis; and 3) community studies. Each of the approaches has its own merits as well as its own shortcomings and the selection of one approach, or several approaches combined, needs to be informed by the particular conditions in a given setting. We argue that hma should always be based on sound impact-assessment practices, but also that it is important to encourage a general understanding of broader impact issues—as opposed to narrow output definitions—among all relevant stakeholders. In spite of considerable progress over the past few years on this issue, impact in mine action is still largely perceived as an event rather than an integral part of the process and specialised units responsible for impact assessment isolate this activity from day-to-day field management.