Book excerpt: We organize things. We organize information, information about things, and information about information. Organizing is a fundamental issue in many professional fields, but these fields have only limited agreement in how they approach problems of organizing and in what they seek as their solutions. The Discipline of Organizing synthesizes insights from library science, information science, computer science, cognitive science, systems analysis, business, and other disciplines to create an Organizing System for understanding organizing. This framework is robust and forward-looking, enabling effective sharing of insights and design patterns between disciplines that weren't possible before. The 4th edition of this award-winning and widely adopted text adds content to bridge between the foundations of organizing systems and the new statistical and computational techniques of data science because at its core, data science is about how resources are described and organized. The 4th edition reframes descriptive statistics as organizing techniques, expands the treatment of classification to include computational methods, and incorporates many new examples of data-driven resource selection, organization, maintenance, and personalization. The Core Concepts edition is an abridged version that is simpler to read because it does not tempt the reader with the deep scholarly web of endnotes contained in the Professional edition. Instead, it seeks to reinforce the concepts and design patterns with numerous "Stop and Think" exercises, and omits some of the theoretical nuance of the Professional edition to put more emphasis on concrete examples.