The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), is the 2013 update to the Diagnostic and Statistical Manual of Mental Disorders, the taxonomic and diagnostic tool published by the American Psychiatric Association (APA). In 2022, a revised version (DSM-5-TR) was published. In the United States, the DSM serves as the principal authority for psychiatric diagnoses. Treatment recommendations, as well as payment by health insurance companies, are often determined by DSM classifications, so the appearance of a new version has practical importance. However, some providers instead rely on the International Statistical Classification of Diseases and Related Health Problems (ICD), and scientific studies often measure changes in symptom scale scores rather than changes in DSM-5 criteria to determine the real-world effects of mental health interventions. The DSM-5 is the only DSM to use an Arabic numeral instead of a Roman numeral in its title, as well as the only living document version of a DSM.

The DSM-5 is not a major revision of the DSM-IV-TR, but the two have significant differences. Changes in the DSM-5 include the re-conceptualization of Asperger syndrome from a distinct disorder to an autism spectrum disorder; the elimination of subtypes of schizophrenia; the deletion of the "bereavement exclusion" for depressive disorders; the renaming and reconceptualization of gender identity disorder to gender dysphoria; the inclusion of binge eating disorder as a discrete eating disorder; the renaming and reconceptualization of paraphilias, now called paraphilic disorders; the removal of the five-axis system; and the splitting of disorders not otherwise specified into other specified disorders and unspecified disorders.

Many authorities criticized the fifth edition both before and after it was published. Critics assert, for example, that many DSM-5 revisions or additions lack empirical support; that inter-rater reliability is low for many disorders; that several sections contain poorly written, confusing, or contradictory information; and that the pharmaceutical industry may have unduly influenced the manual's content, given the industry association of many DSM-5 workgroup participants. The APA itself has published that the inter-rater reliability is low for many disorders, including major depressive disorder and generalized anxiety disorder.

The DSM-5 is divided into three sections, using Roman numerals to designate each section.

Section I describes DSM-5 chapter organization, its change from the multiaxial system, and Section III's dimensional assessments. The DSM-5 dissolved the chapter that includes "disorders usually first diagnosed in infancy, childhood, or adolescence" opting to list them in other chapters. A note under Anxiety Disorders says that the "sequential order" of at least some DSM-5 chapters has significance that reflects the relationships between diagnoses.

The introductory section describes the process of DSM revision, including field trials, public and professional review, and expert review. It states its goal is to harmonize with the International Statistical Classification of Diseases and Related Health Problems (ICD) systems and share organizational structures as much as is feasible. Concern about the categorical system of diagnosis is expressed, but the conclusion is the reality that alternative definitions for most disorders are scientifically premature.

Section II contains chapters describing types of mental disorders, such as dissociative, neurodevelopmental, and personality disorders. The chapters begin with a description of the group of disorders in question, followed by the specific diagnoses, such as dissociative identity disorder or autism spectrum disorder. For each disorder, a set of diagnostic criteria is presented, followed by descriptions regarding things such as of diagnostic features and prevalence, as well as a list of other disorders to consider for a differential diagnosis, along with descriptions of the differences between these.

Section III includes dimensional measures for the assessment of symptoms, criteria for the cultural formulation of disorders and the Alternative DSM-5 Model for Personality Disorders – a hybrid-dimensional-categorical model of personality disorders, as well as a description of the currently studied clinical conditions. It presents selected tools and research techniques focused on diagnosis, taking into account the sociocultural context.^{[citation needed]}