A monograph is a detailed essay or book on a very specific, often limited subject. It is designed to stand alone, and is usually not part of a series, unless the monograph is being released in several parts. Research libraries usually have a large collection of monographs, and an academic department at a university may also have an assortment of monographs published within its subject. In general, a monograph is very dense with information, and is of little interest to people outside the field.

In order to gain respect within the academic community and tenure at a major university, an academic must publish monographs over the course of his or her life. These scholarly treatises provide evidence that the academic is carrying out research in the field and analyzing already published information. A monograph usually brings new light to the subject, and it may contain breakthrough research. It also further refines the academic specialty of the author, and establishes the author as an authority on the topic.

Usually, only one author is behind a monograph, although two academics may collaborate if they have been carrying out research together. A monograph is also only published once, as a general rule, unless it catches on as a textbook. Very rarely, a monograph will be of interest to a larger community, meriting a slightly bigger print run to meet demand. Because the print runs are very small, within several years of publication it can be difficult to obtain a copy of a monograph.

A topical book, such as an overview of European history, is not a monograph. A book discussing Venetian glass might be, if it was a detailed and thoroughly researched history. The guiding principle behind a monograph is that it should contain highly original material which will be of use to people working within a limited field. Entomologists, for example, might publish monographs on single insect species, designed to demonstrate their extensive knowledge of the species in question and to educate others in the field.

When a monograph takes the form of an essay, it is typically published in an academic journal. Books are published by university presses or small presses, although the monograph in book form began to struggle in the 1990s. Rising costs of publication began to make it highly impractical to publish costly books with limited print runs and potential interests. The Association of Research Libraries held a conference in 1997 to discuss the future of the monograph, and ways in which it could be saved.