The objective of this paper is to present an overview of ethnicity, ethnic strife and its consequences, as seen from the perspective of the disciplines of economics, political science, social anthropology and sociology. What exactly is ethnicity--how is it to be defined, characterized and measured? What exactly are the causal links from ethnicity so defined to its presumed consequences, including tension and violence? What are the feedback loops from the consequences of ethnic divisions back to these divisions themselves? How can policy, if at all, mitigate ethnic divisions and ethnic conflict? Finally, what role does interdisciplinarity have in helping to understand ethnicity and ethnic strife, and how can interdisciplinary collaboration be enhanced? These are the questions which this paper takes up and deals with in sequence.