“Evaluation” is not such a bad word. It is about making a judgment about the value of something. To make such a value judgment, you need to be in learning mode. Curiosity will serve you well. In this book by Gil Rendle, you are provided with a toolbox to help you clarify the purpose of your congregational endeavors and how to measure their effectiveness. These are tools that will help you learn from your ministry. The author wants to help you turn good ideas into outcomes. Rendle serves as senior consultant with the Texas Methodist Foundation in Austin, Texas. Previously, he served the Alban Institute as an author, seminar leader and senior consultant. Among the many helpful observations in the book is the difference between counting and measuring. Rendle notes that “counting is giving attention to numbers… measuring is giving attention to change.” Both are important, but in different ways. This book will help you discern the ways in which your congregation makes a difference in lives. Doing the Math of Mission is about how you measure the purposefulness of your congregation. It will help you equate evaluation with learning. It will support your curiosity about doing the math of mission.