Between 1756 and 1840, philanthropy in the British world grew from the domain of small, associational committees to a vast enterprise of philanthropic and humanitarian societies with global reach. British Philanthropy in the Globalizing World tells the story of this movement, from its inception in small networks of mercantile and religious entrepreneurs to its signal projects and achievements in the abolition of slavery, in evangelical missionary societies, Bible societies, and in the early indigenous rights movement. It traces the lives and networks of hundreds of philanthropists across four generations, showing how their social, religious, economic, intellectual, and cultural worlds intersected to foster philanthropic innovation through organisational models, transnational networks, and the creation of a unique formative culture. It shows how groups such as the Clapham Sect -- including William Wilberforce, Henry Thornton, Hannah More, James Stephen, and others -- emerged in an intergenerational context, and how they sought to effect social and cultural change across multiple spheres. For every headline achievement, there were many failed experiments, inner wrestlings, and long-running intellectual collaborations that left a wide and deep imprint on the cultural and political landscape of the English-speaking world. Drawing on the separate historiographies of metropolitan philanthropy, associational culture, anti-slavery, moral reform, Evangelicalism, colonial missions, and economic thought, the study unites into one analytical frame both the imaginative and organizational realities of philanthropy, offering a dual focus on individual philanthropists -- their inner lives, daily practices, and participation in collaborative communities -- and on mapping the networks that bound philanthropic societies and projects together in metropolitan London and at the far reaches of the British world. In doing so, it offers a very human portrait of these entrepreneurs and evangelicals, as they pursued a philanthropic global vision.