The stated goals of Structures for Organizing Knowledge: Exploring Taxonomies, Ontologies, and Other Schemas are to examine how people organize information in personal and professional contexts; to explore the roles of categories, taxonomies, and other structures in that work; and to understand the human organizing behaviors that should guide the design of useful information structures (xv–xvi). The book is intended both for students and scholars studying information organization and for information professionals seeking inspiration for and insight into the design of organizational structures. In keeping with its potential use as a textbook, each chapter begins with a summary statement of themes and concludes with a set of “thought exercises.” Along the way, readers are directed to other sources for more in-depth treatment of particular topics.

The book is divided into three parts. Part 1 studies the traditional structures used to organize information, including both structures used to describe particular resources (such as the MARC record) and those used to organize concepts ranging from the very general to the highly specific. Abbas's account of the familiar tools of library science—subject lists, controlled vocabularies, classification systems, etc.—is followed by an analysis of classification systems developed in the natural sciences and by a discussion of cognitive science's reformulation of categories as structures based on the observers’ variable perceptions of “family resemblances,” and not simply on a binary logic of sameness and difference. Part 1 also covers the standards environment responsible for developing and maintaining many of the traditional structures and the importance of guidelines for application of standards-based structures. Part 1 accounts for roughly 60 percent of the text, which reflects the diversity, depth, and complexity of traditional organizing practices in the various disciplines examined.

Part 2 examines the ways individuals organize information in personal and professional settings. The author reviews research in both areas, noting such interesting findings as the limited effort people devote to organizing their own information space, the tendency of that space to be occupied by unintentional accumulations, and the importance of intended use and frequency of use to personal classification decisions. Abbas notes a preponderance of studies of how successfully people adapt to new organizational design prototypes, but a lack of research “into how people organize their paper-based and digital information” (167) and the absence of such supplied structures. Research into “the structure(s) we employ for organizing personal information in both work and nonwork environments may reflect how we conceptually think about and structure the routines, tasks, projects, etc., that we are engaged in on a daily basis and over a lifetime” (162). This quest for a deeper understanding of the “natural” organizational impulses of human beings is a running theme of the book. Yet “natural” behavior is perhaps not a major driver for some organizational behavior. More might have been said about the additional factors that come into play when structures for information organization are intended to be built and shared by communities.

Part 3 turns to the emerging study of socially based knowledge-organization tools, including LibraryThing, Flickr, and YouTube. The structures examined in this section include user tags, social bookmarking, folksonomies, and others, deployed in different combinations by different Web 2.0 applications. As user choices accrete in these environments, they drive the development of community preferences for particular models of terminology and socially based ranking. Yet the advantages of flexibility can be offset by the disadvantages of inconsistency and lack of consensus. Abbas observes that while the studies in part 3 “provide us with a window into how people naturally will organize objects in their personal knowledge spaces,” they do not reveal “the structures people prefer for organizing objects” within these spaces (200).

In the last two chapters, Abbas explores how insights from the three areas discussed might be combined to provide a basis for designing more flexible and useful organizing structures. She notes that while the tools of socially constructed knowledge organization have been introduced into such traditional structures as the online catalog, little empirical evidence has emerged to prove that users find this combination useful and that further research into the management of tags and folksonomies is needed. She also argues for giving more attention to a fourth “thread” in the pattern being woven, highlighting not just the structures of socially based information, but their participatory aspect and value as users’ voices engage with providing new contexts for understanding information objects.

In her Preface, Abbas writes,

The book is not meant to be a “how-to” guide for developing, applying, or implementing structures for organizing knowledge; rather, it is designed to present a conceptual discourse and to inspire thinking about taxonomic behavior, or how and why people organize knowledge, in various contexts. (xix)

Structures for Organizing Knowledge succeeds on these terms, providing both a thoughtful survey of research findings and a stimulating complex of issues to ponder. Inevitably, some topics are slighted; for example, relatively little is said about the potential of the Semantic Web and open linked data as a new structural model for organizing information. This does not detract from the valuable contribution Abbas makes in this book to the study of knowledge organization.