In light of the growing complexity of humanitarian crises today and the continued need for effective cooperation among humanitarian actors, the International Committee of the Red Cross (ICRC) and the Office of the United Nations High Commissioner for Refugees (UNHCR) launched a consultative process in September 2016 to collect operational practices with regard to maintaining the civilian and humanitarian character of sites and settlements for internally displaced persons (IDPs) and refugees. Exchanges with field staff from both organizations targeted five ongoing operations–in the Central African Republic (CAR), the Democratic Republic of the Congo (DRC), Iraq, Nigeria and South Sudan – and included a one-day workshop in Geneva on 20 April 2017 in which the UN Department of Peacekeeping Operations (DPKO) also participated. A wider set of stakeholders was consulted as well, during a roundtable organized under the auspices of the Global Protection Cluster (GPC) on 21 April.This aide-memoire draws on the above-mentioned consultations to provide operational guidance for humanitarian actors in maintaining the civilian and humanitarian character of sites and settlements (hereinafter referred to as sites) in situations of armed conflict. Part 1 of this guidance sets out the necessary context and principles with regard to the civilian and humanitarian character of sites. It provides a description of the main operational challenges and dilemmas that humanitarian actors confront and examines the content of applicable legal frameworks. Part 2 offers measures for humanitarian actors to consider – within the remit of their respective expertise, experience and mandates – when working toward maintaining the civilian and humanitarian character of sites. These measures include efforts to engage actors beyond the humanitarian community in the spirit of complementarity and in respect of humanitarian principles.