Operation World is an AMAZING book for all the people groups in the world. I use this book daily. LOVE IT! A NEW edition is available out now. You can order it from Barnes and Noble by clicking here. This book goes through different countries and shows the location, primary religion, challenges, stories of Christians in that particular country, and how to pray specifically for the country. I love how you can be a part of ALL NATIONS with this book. I love how you can pray for needs of ALL NATIONS with this book.