EU Member States are increasingly involved in border management activities on the high seas, within – or in cooperation with – third countries, and at the EU’s borders. Such activities entail risks of violating the principle of non-refoulement, the cornerstone of the international legal regime for the protection of refugees, which prohibits returning individuals to a risk of persecution. This guidance outlines specific suggestions on how to reduce the risk of refoulement in these situations – a practical tool developed with the input of experts during a meeting held in Vienna in March of 2016.