Handbooks and companions are a stock-in-trade for academic researchers. Typically, they're edited volumes, with chapters written by (often commissioned from) subject experts. They synthesize current "consensus" thinking about  a particular topic, phenomenon, theory, etc., and often offer extensive bibliography. 

Certain publishers (Oxford UP, Cambridge UP,  Blackwell, Routledge, and Sage) are well-known for producing high quality, authoritative handbooks on a wide array of topics across the disciplinary spectrum. 

PRO-TIP: One easy way to search for them is simply to add the word "handbook"  or "companion" or "reader" or even "introduction" to a broad keyword search in HOLLIS. That's because they often have this word in the title (signifying form as as well as content) or because they a have special language tag added to the catalog description.

Examples: 

Cambridge Companion to Critical Theory

In this volume an international team of distinguished contributors examines the major figures in Critical Theory, including Horkheimer, Adorno, Marcuse, Benjamin, and Habermas, as well as lesser known but important thinkers such as Pollock and Neumann. The volume surveys the shared philosophical concerns that have given impetus to Critical Theory throughout its history, while at the same time showing the diversity among its proponents that contributes so much to its richness as a philosophical school. The result is an illuminating overview of the entire history of Critical Theory in the twentieth century, an examination of its central conceptual concerns, and an in-depth discussion of its future prospects.

Cambridge History of Twentieth. Century Political Thought 

Provides a comprehensive overview of the development of political thought from the late nineteenth to the end of the twentieth century: covers the rise of the welfare state and subsequent reactions to it, the fascist and communist critiques of and attempted alternatives to liberal democracy, the novel forms of political organization occasioned by the rise of a mass electorate and new social movements, the various intellectual traditions from positivism to post-modernism that have shaped the study of politics, the interaction between western and non-western traditions of political thought, and the challenge posed to the state by globalization.

Oxford Handbook of Feminist Theory (2015)

Leading scholars from across the globe provide an overview of the analytical frameworks and concepts feminist theorists have developed to challenge key epistemic assumptions that inform traditional scholarship. The chapters offer innovative analyses these transformations on  topics in social and political science, cultural studies and the humanities, discourses in medicine and science and contemporary critical theory.  

Oxford Handbook on Philosophy and Race (2017)

Provides up-to-date explanation and analyses by leading scholars of contemporary issues in philosophy of race and African American philosophy. Ideas about race held by Locke, Hume, Kant, Hegel, and Nietzsche are supplemented by suppressed thought from the African diaspora, early twentieth-century African American perspectives, and Native American, Asian American, and Latin American views. Philosophical analysis is brought to bear on the status of racial divisions as human categories in the biological sciences, as well as within the architectonic of contemporary criticism and conceptual analysis. The special applications of American philosophy and continental philosophy to ideas of race are presented as methodological alternatives to more analytic approaches. 

Sage Handbook of Philosophy of Social Sciences (2011)

Starting with the history of social scientific thought, this handbook sets out to explore the core fundamentals of social science practice, from issues of ontology and epistemology to issues of practical method.  Considers the contrasting approaches by which social scientists study the world and justify their knowledge claims and  identifies the fissures and debates in contemporary thought.

Stanford Encyclopedia of Philosophy: a well-respected web resource. Entries are created and maintained by groups of experts and materials are peer-reviewd by a distinguished editorial board prior to their publication. Essays cover individuals, concepts, and events related to all aspects of philosophy. Each article has a list of references to other sources, including books and journal articles;

The International Encyclopedia of the Social and Behavioral Sciences, first published in 2001 and completely revised in 2015, is an effort to map the map the social and behavioral sciences on a grand scale. As such, it is a vast, authoritative, and efficient first point of entry for researchers. 

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