The objective of the present study was to develop and assess the validity of a short form of the Child-Adolescent Perfectionism Scale (CAPS). Two Portuguese samples composed of 756 adolescents were used to cross-validate the factorial structure of a nine-item Child-Adolescent Perfectionism Scale--Short Form (CAPS-SF). The CAPS-SF consists of a four-item self-oriented perfectionism subscale and a five-item socially prescribed perfectionism subscale. Both subscales demonstrated adequate internal consistency. Confirmatory factor analysis (CFA) of the CAPS-SF supported the same two-factor structure and represented a very good fit to the data for both groups. Other analyses found that the brief measure of socially prescribed perfectionism was associated with measures of distress and forms of self-criticism. The CAPS-SF appears to represent a reliable and valid alternative to the original CAPS. Overall, the CAPS-SF is considerably briefer than the original CAPS and it offers an economical and valid alternative when measuring perfectionism in children and adolescents.