The ‘Snodgrass affair’ was a long-drawn-out legal controversy, which began in 1762 and continued with interruptions until 1776. Its origins lay in a sermon which the influential Calvinist clergyman John Witherspoon preached when he was a minister in Paisley near Glasgow. In the sermon, which was also subsequently printed, Witherspoon accused several men in his parish of profane and blasphemous conduct. The men who had thus been very publicly exposed by Witherspoon reacted by portraying him as a slanderous zealot. John Snodgrass, after whom the affair was named, was the most active member of that group. In 1763 Witherspoon publicly rebuked Snodgrass a second time, on this occasion for adulterous behaviour. Snodgrass, with several supporters, retaliated by accusing Witherspoon of defamation. Eventually the case was brought before the Edinburgh Court of Session, where it was finally settled in 1776. By that time Witherspoon had been absent from Scotland for several years, having left in 1768 to become Head of the College of New Jersey, later Princeton University. Crawford's book is a meticulously researched account of the affair, which has not been examined in similar detail before. The text includes extensive passages from the main relevant primary sources. Crawford's suggestion that the disappointments that Witherspoon had suffered during the legal affair were important in persuading him to leave for America is not perhaps entirely convincing. However, this book is an essential resource for anyone wanting to understand the course of the Snodgrass affair and Witherspoon's role within it.