The World Health Organization’s Western Pacific Region website invites its visitors to: “Imagine having to deliver health services to a population dispersed across dozens of atolls and island groups, covering a distance of up to 5,000 kilometers, with slow internet, extremely high operational costs as well as infrequent transport links.” One hundred years ago, the British colonial authorities faced the same set of problems in the Pacific. This seminar will discuss the initiatives to promote healthcare in the Pacific Islands in the first half of the twentieth century, with a focus on the British Empire. Colonial administrations in the Pacific Islands connected, cooperated, and competed with one another through an overarching scheme that centralised medical institutions. It was a process that, at various times, involved quarantine, education, disease-control, military medicine, and public health. Together, the centralised medical institutions inaugurated an imperial healthcare system in which constituents of the British Empire engaged in both hierarchical and lateral relationships. The history of the development of healthcare in the Pacific Islands is, therefore, a remarkable example of intercolonial, interimperial, and intraimperial relations.