Henry Venn (1796–1873) was an Anglican clergyman who, like his father and grandfather before him, was influential in the evangelical movement and campaigned for social reform, eradication of the slave trade, and better education and economic progress in the British colonies so as to enable them to become responsible for their own affairs. Venn was Secretary of the Church Missionary Society from 1841 to 1873, and alongside practical training and appointment of missionaries and ministers he spent time developing a theology of mission and principles for its practice. This book, published in its second edition in 1881, was edited by William Knight who had access to Venn's private journals and correspondence (from which he used substantial quotations), and met Venn's niece, who provided the portrait of her uncle used as the frontispiece of the book. The appendix contains some of Venn's own accounts of his early missionary work.