Sexual minorities are at a greater risk for experiencing a serious mental illness (SMI) compared to heterosexuals, and sexual minorities suffering from a SMI experience stigma and discrimination that leads to a greater need for counseling services. Current research does not address the needs of sexual minorities with a SMI and how to prepare counselors to work with this population, as most sexual minorities with a SMI find that counseling services do not meet their unique needs. The purpose of this transcendental phenomenological study, grounded in a Husserlian philosophical and minority stress model conceptual framework, was to explore the experiences and perceptions of counselors who provide counseling services to sexual minorities with a SMI. Data were collected from six participants using semistructured interviews and followed a thematic data analysis process, ensuring thematic saturation. The results of this study highlighted many themes regarding the unique needs of sexual minorities with a SMI such as multiple minority stressors, negative counseling experiences, and the impact of family, as well as counselors' perceptions regarding the lack of preparation in graduate school to work with sexual minorities with a SMI. Study findings may improve counselors' understanding of the needs of sexual minorities with a SMI so they may provide more effective counseling services. This study also highlights the importance of training counselors to work with this population and may support the efforts of counselor educators.