Good, short, old (quotes Barth as a contemporary), non-scholarly book covering the Reformed view of the sacraments. Written with ministers in mind, he spends many pages giving suggestions on how a service may best fit the reality of the sacraments. Not an amazing read, but practical.
This book is not an in depth scholarly study of the sacraments. It is instead an overview of the sacraments approached from a Presbyterian Ministers perspective in the 1940's. Kerr focuses on the very foundation stones of the sacraments asking questions like "What is to be represented in baptism and communion?" and "What are the various views of these sacraments?"
Where this book excels is in its emphasis on "what do these things teach us." He also does a great job of focusing on how we need to recapture the teaching elements of these sacraments from the pulpit and for our children. Another thing he does well, especially in the last chapter, is when he talks about open communion and the various position from various denominations.
This book is a great small read that really gets you asking some questions that could benefit anyone he loves the sacraments, especially those who administer these means of grace.