This work comprises a detailed study of Bucer's thinking on ecclesiastical office. The Strasbourg reformer exercised a great influence on Calvin, among others. This exploration does not only contribute to the knowledge of the body of thoughts and views of this often ignored reformer, whose importance is increasingly being recognised. It also contains a large amount of material which is extremely valuable for current discussion - theological and practical - on office and structure within the Church.The author has based his research on various rare editions found in libraries all over Europe. He also used many unpublished sources from the abundant archives in Strasbourg.