Ethical concerns are rising in the business world. With this in mind, training and performance improvement practitioners, especially during evaluation projects, should be aware of principles and codes of ethics, and their behaviors and decisions should reflect the standards recognized by members of the professional society. A study was conducted with 108 training and performance improvement practitioners to reveal the reasoning behind their judgments of ethically challenging evaluation situations and to understand their rationales through the lens of existing guiding principles. Participants read three scenarios and judged the ethicality of the evaluator's actions in each scenario. Results revealed that participants who were aware of both the International Society for Performance Improvement's Code of Ethics and American Evaluation Association's Guiding Principles for Evaluators were stricter in their judgments about the ethicality of one scenario than those who were not. This article discusses implications of the results and higher education's role in reinforcing an ethical culture and ethical practice by employees. (Contains 11 tables and 1 figure.)