Counselors are required to have high levels of social-cognitive development, significant knowledge regarding ethical and legal practice, and sound ethical decision-making processes to provide effective and ethical services to their clients. This study investigated the effect of two counseling ethics courses on 64 master's-level counselor education students' levels of social-cognitive development, ethical and legal knowledge, and ethical decision making. Students' ethical and legal knowledge scores increased significantly, and precourse social-cognitive maturity predicted postcourse ethical and legal knowledge scores. Implications for counselor education and development are discussed.Many dynamic processes are inherent to the field of counseling. To effectively negotiate the fluid interactional processes that occur in counseling, professionals are required to navigate a complex knowledge base of ethical and legal tenets that underlie their practice, as well as engage in informed ethical decision making. Theoretically, counselors' ethical and legal knowledge and ethical decision making should be influenced by their level of social-cognitive development. A primary component of counselors' preparation, therefore, is the purposeful promotion of counseling students' social-cognitive development, which is associated with greater empathy, flexibility, perspective-taking, self-care, and wellness