The Four Agreements, was published in 1997 and has sold around 5.2 million copies in the U.S. and has been translated into 38 languages.
The book advocates personal freedom from beliefs and agreements that we have made with ourselves and others that are creating limitation and unhappiness in our lives.
The Four Agreements are:
1 - Be impeccable with your word.
2 - Don't take anything personally.
3 - Don't make assumptions.
4 - Always do your best.