This book investigates the origins, evolution, and contemporary application of the term 'fundamentalism' to determine if it serves as a coherent descriptor for diverse global movements. Author Malise Ruthven, a recognized expert on Middle Eastern affairs, utilizes a multidisciplinary approach to dissect the term's history from its 1920s American Protestant roots to its current usage. By examining the political, religious, and social contexts of various radical groups, Ruthven argues that the label is often applied inconsistently to a wide array of ideological purists. The text provides a framework for distinguishing between genuine theological movements and broader political radicalism.

Experts and academics frequently cite this work as a foundational, accessible primer for understanding the complexities of modern religious and political extremism. Readers often note that the prose is concise and objective, making it an effective resource for navigating a highly polarized subject area.