The ethics of practice diversification in the field generically described as performance psychology--including sport psychology, organizational consulting, and performing arts psychology--is examined. Since the field is in the process of development and psychologists come to this type of practice from a variety of paths, ethical issues in this type of practice bear particularly careful attention. This article reviews the primary ethical issues involved, including preparation for diversified practice; competence; interpersonal and relational issues; and presentation to the public. Currently emerging concerns are also discussed. The article concludes with specific suggestions for the practitioner interested in this field.