This two-phase, sequential mixed methods study explored how student affairs professionals resolved professional ethical dilemmas. A student affairs professional was defined as an individual whose educational background and work experience are in student affairs. An ethical dilemma is defined as a situation in which two ethical principles are at odds rather than a simple matter of right versus wrong (Kitchener, 1985). A professional ethical dilemma is an ethical dilemma in the context of a person's work-related experience. The first phase of the study was a qualitative exploration of how representatives of the Council for the Advancement of Standards in Higher Education (CAS) resolve professional ethical dilemmas by interviewing the representatives. The second phase of this study was confirmatory. An online questionnaire was designed and administered to members of the National Association of Student Personnel Administrators (NASPA) who held positions similar to those held by the phase one sample. The questionnaire was designed to confirm the findings from phase one about ethical dilemma resolution. The study found that professional ethical dilemmas are very complex, involving multiple ethical principles, multiple roles of the person facing the dilemma, and multiple constituent groups involved in the dilemma. Despite this complexity, student affairs professionals use a relatively simple resolution process of serious reflection and conferring with others. Considerations of self (e.g. role in dilemma and impact on self) and the wider organization (e.g. legal implications and political implications) were used in the resolution process. The study also found that student affairs professionals' personal values helped them prioritize the vying ethical principles involved in the dilemma so that they could make a decision that they believed was ethical. / Ph. D.