Individual Psychological Assessment (IPA) is a very widely offered service in Organizational Psychology. It generally consists of a psychologist or HR practitioner using a combination of interview and psychometrics to arrive at a detailed assessment of an individual's capabilities in relation to a job they are being considered for. Although much used, this practice has limited supporting evidence of its validity—not least because of the methodological difficulties in conducting research on this subject—and has been criticized accordingly. The current study examines the use of IPAs with 115 middle and senior management level candidates in a civil service context. All candidates completed a set of psychometric measures and had an in‐depth interview with a psychologist as part of a standardized process. The ratings made by the assessors were correlated with a criterion measure of potential for promotion derived from multisource feedback ratings obtained on these candidates some months later. Analysis of the results indicated that three of the four attributes rated by assessors correlated significantly with the criterion measure. Further, assessors’ ratings were found to show incremental validity over that provided by psychometric test scores alone. These findings are discussed in terms of the use of IPAs in senior level assessment.