Introduction: Suicidal and self-injurious behaviors in adolescents are a major public health concern. However, the prevalence of self-injurious thoughts and behaviors in Spanish outpatient adolescents is unknown., Methods: A total of 267 adolescents between 11 and 18 year old were recruited from the Child and Adolescent Outpatient Psychiatric Services, Jiménez Díaz Foundation (Madrid, Spain) from November 1st 2011 to October 31st 2012. All participants were administered the Spanish version of the Self-Injurious Thoughts and Behaviors Inventory, which is a structured interview that assesses the presence, frequency, and characteristics of suicidal ideation, suicide plans, suicide gestures, suicide attempts, and non-suicidal self-injury., Results: One-fifth (20.6%) of adolescents reported having had suicidal ideation at least once during their lifetime. Similarly, 2.2% reported suicide plans, 9.4% reported suicide gesture, 4.5% attempted suicide, and 21.7% reported non-suicidal self-injury, at least once during their lifetime. Of the whole sample, 47.6% of adolescents reported at least one of the studied thoughts or behaviors in their lifetime. Among them, 47.2% reported 2 or more of these thoughts or behaviors. Regarding the reported function of each type of thoughts and behaviors examined, most were performed for emotional regulation purposes, except in the case of suicide gestures (performed for the purposes of social reinforcement)., Conclusions: The high prevalence and high comorbidity of self-injurious thoughts and behaviors, together with the known risk of transition among them, underline the need of a systematic and routine assessment of these thoughts and behaviors in adolescents assessed in mental health departments., (Copyright © 2013 SEP y SEPB. Published by Elsevier España. All rights reserved.)