The Companion to the Constitution: Polity for the Local Church by Frank A. Beattie is a valuable resource for Presbyterians seeking to understand the church's Constitution and its implications for local church governance. The book serves as a guide to Presbyterian law and procedures, addressing the needs of church sessions and providing a better understanding of the church's Constitution and how it works. It is intended to be an aid to education and understanding, with revisions made as the Constitution is interpreted and amended.