Motivational interviewing (MI) is effective in the treatment of addictions. To evaluate MI adherence of therapists, the Motivational Interviewing Treatment Integrity Code (MITI) was developed. MI is used in German-speaking countries, but there is no equivalent to the MITI. Our aim was to adapt the MITI for use in German language settings (MITI-d). Twenty-eight session tapes of Alcoholism Specific Psychotherapy utilizing MI were rated by two student raters and the MITI-d instructor. To evaluate interrater reliability, intraclass correlation coefficients (ICCs) were computed. ICCs were good to excellent for relevant MI constructs, except for Complex Reflections, MI-nonadherent Behaviors, Empathy, and MI Spirit. The evaluation of test-retest reliability for the student raters showed good to excellent results. The MITI-d is a psychometrically sound instrument for evaluating basic MI competence in German language settings.