The current study examined temperament characteristics as risk factors for restraint and seclusion (R/S) events in psychiatrically hospitalized youth, extending work that has sought to identify R/S risk factors and research examining temperament-behavior problem associations that has largely relied upon community samples. It was anticipated that children with poor effortful control (EC) and greater frustration would have more instances of R/S during psychiatric hospitalization. The contribution of children's fearfulness to R/S was also examined. A measure of temperament was completed by youths' clinicians and youths (n = 52) completed objective measures of EC. The frequency of R/S events for each participant was obtained from hospital records. After controlling for R/S risk factors, lower EC and higher fearfulness predicted increased R/S occurrences during the first 2 weeks of hospitalization and over the course of children's entire hospitalization. These findings indicate that temperament should potentially be considered in individualized treatment plans targeting the prevention and/or reduction of R/S. Additional implications of the findings are also discussed.