This is a great book. It tells the story of the history of beer, the story of Christianity's historically close relationship with beer, the story of Guinness beer, and the story of the Guinness family. If it weren't for modern evangelicalism's condemnation of alcohol in all forms, I'm sure this story would have been told years ago.
The water in many parts of the world has been undrinkable throughout history. Recognizing the dangers of drunkenness, many Christians throughout history have brewed beer as an alternative to hard liquor. Arthur Guinness was part of this great Christian tradition of brewing beer. He recognized that brewing was not just a job to earn money, but a vocation--a calling from God. He worked diligently to create a high quality beer. He was very successful and he and his family used the wealth to serve their neighbor. Guinness workers received higher wages and all kinds of extra perks. The family also used the wealth to serve the community around them.
The book has a nice section on the idea of vocation as well as ways to apply principles used by Arthur Guinness. There are a few typos but the book is very well-written.