This article discusses the integrative review of the literature as a distinctive form of research that uses existing literature to create new knowledge. As an expansion and update of a previously published article on this topic, it acknowledges the growth and appeal of this form of research to scholars, it identifies the main components of the integrative literature review, and summarizes guidelines for organizing and writing integrative literature reviews. Not addressed elsewhere in the literature, this article describes five reasons and purposes for writing literature reviews and discusses these purposes in relation to the methods for writing literature reviews. The article concludes that aligning the integrative literature review's methods with its purpose provides unity and coherence to the review.