Today all would agree that Mexico and the United States have never been closer--that the fates of the two republics are inextricably intertwined. It has become an intimate part of life in almost every community in the United States, through immigration, imported produce, business ties, or illegal drugs. It is less a neighbor than a sibling; no matter what our differences, it is intricately a part of our existence.

In this outstanding contribution to Oxford's acclaimed series, What Everyone Needs to Know(R), Roderic Ai Camp gives readers the most essential information about our...