The provision of non-audit services by the statutory auditor may have a negative impact on independence in mind as well as on independence in appearance. Prior research revealed that different advisory services have a different effect on perceived auditor independence. This could be caused by the fact that a differnt number and intensity of endependence threats is attached to indiviual services. Therefore this experimental study investigates the effect of such threats on independence perceptions of German individual investors. The results show that the selfreview and the familiarity threat may impair auditor independence disregarding their size. Furthermore, it was found that a higher self-review threat increases the negative impact on independence perceptions. an advocacy threat, however, seens to be irrelevant. Manipulation checks disclose that the manipulation of the familiarity chedk failed. Thus, related conclusions must be drawn with care.