Selective mutism (SM) is a childhood anxiety disorder characterized by a persistent failure to speak in specific social situations, most commonly school, despite the ability to speak comfortably in other settings, particularly at home (Muris and Ollendick, 2021). Classified in the DSM-5 (American Psychiatric Association [APA], 2013 in 2022) and ICD-11 (World Health Organization [WHO], 2018) as an anxiety disorder, SM typically emerges before age 5 and comes to clinical attention when children enter formal schooling, and can persist into adulthood without treatment. Research across the past decade has significantly advanced understanding of SM's etiology, assessment, comorbidities, and treatment, with the most recent meta-analyses confirming that face-to-face behavioral interventions produce large and durable effects (Iimura et al., 2025). This article reviews the definition and diagnostic criteria, prevalence and epidemiology, etiology, comorbidities, assessment practices, treatment approaches, and long-term outcomes. Future directions are also highlighted.
