To distinguish tribes and tribal societies from tribalism, it's important to know about tribes, tribalism, tribal behavior, and why tribes are important in some countries. In this scholarly work, the author examines the origin of tribes and why it is necessary to have tribes in several cultures. In addition, the book provides empirical evidence that links tribalism to ethically suspect behaviors, such as unfairness, dishonesty, a lack of equity, and corruption. The author explains why globalization has reduced corruption in many governments worldwide. Generally speaking, the author argues a myriad of reasons cause people in tribal countries to behave unethically, including tribalism and other tribal consequences such as oppression. Other topics include: the history of ancient tribes, the importance of tribes for several societies, tribal identity, and why people are blindly loyal to a tribe. Filled with examples, the book explains why tribalism is a cultural behavior different from other cultural values. The author also argues that researchers should consider adding tribalism to Hofstede's Cultural Values that differentiate societies from one another. The book includes a tribalism measure for those who want to measure tribalism at the individual level.