Yancey takes a shot at tackling the subject of doubt, and gives a thoughtful and at times personal account of his thoughts on the subject. I liked the book overall, and Yancey definitely gives voice to both the doubts and the answers to those doubts, at least for him. I like his use of illustrations from his travels and from his various experiences. The book is a good one, and gives the reader a lot to consider in one's own struggle with doubt. Still, I felt that Yancey doesn't doubt very much, or if he does, he doesn't go deep enough in exploring more serious doubts about God. I think the book is good for people who are already Christians and who wrestle with some light doubting. But for seekers who do not already accept much of what Christians take for granted, Yancey does not go deep enough in describing doubt or how to overcome it. Perhaps that was not his intent in this book, certainly others have attempted it and come up short. For Christians wishing to deepen their faith and be challenged in overcoming doubt, this book delivers nicely. For those struggling with serious doubt, I think this book can help but readers may want to look elsewhere for a more indepth study.