How and why have activists launched initiatives in support of people who were often far removed from them? The journal issue seeks to answer this question, casting a critical eye on the construction of humanitarian causes. The authors draw attention to the different rationales for humanitarian activism: from compassion and solidarity to self-interest. They also examine how activists viewed and represented the objects of their campaigns. The contributions thus investigate what aid efforts can tell us about the self-perception of those who engaged in them. The coverage ranges from the early nineteenth century to the 1970s. Although the historical contexts differ, a number of shared themes emerge. One is the way in which activists used dramatic appeals to attract attention for their cause. Another aspect is the use or transformation of existing associational structures in the face of events that were seen as emergencies. Finally, the articles highlight the political sub-texts of endeavours that the activists themselves tended to portray as ‘apolitical’.