The relationship between childhood trauma and adult psychopathology has been explored in the literature. The goal of this study is to compare existing instruments that measure retrospective interpersonal gross childhood trauma. A computerized search from 1985 to March 2003 was performed to locate instruments used to measure childhood trauma. These were divided into interview-rated and self-report measures and were compared on various parameters. Twenty-one observer-rated and 21 self-report instruments were identified. In a comparison, five observer-rated measures and three self-report measures stand out for having favorable characteristics such as assessing multiple types of trauma and reporting on psychometric properties. A number of instruments are designed to measure a single type of trauma, usually sexual abuse, but most of these do not report psychometric properties. A few instruments used to measure retrospective childhood trauma are particularly useful for systematic research in adult psychiatric disorders.