This study simultaneously assessed the inter‐rater reliability of the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders Axis I (SCID I) and Axis II disorders (SCID II) in a mixed sample of n = 151 inpatients and outpatients, and non‐patient controls. Audiotaped interviews were assessed by independent second raters blind for the first raters' scores and diagnoses. Categorical inter‐rater reliability was assessed for 12 Axis I disorders of SCID I, while both categorical and dimensional inter‐rater reliability was tested for all Axis II disorders. Results revealed moderate to excellent inter‐rater agreement of the Axis I disorders, while most categorically and dimensionally measured personality disorders showed excellent inter‐rater agreement. Copyright © 2010 John Wiley & Sons, Ltd.

• Elaborate training in administration of the Structured Clinical Interview for DSM disorders (SCID) is a crucial ingredient for valid use of the SCID.

• The more dimensionally the SCID II pathology is indexed, the higher inter‐rater reliability.

• Structural assessment of Axis I and Axis II pathology by means of SCID I and II is an essential ingredient for valid and reliable pathology assessment in clinical practice and in research.