Individuals who identify as transgender or gender nonconforming (TGNC) face a number of health disparities compared to individuals who identify as cisgender (those who self-identify with the sex they were assigned at birth). For example, TGNC individuals experience heightened rates of clinical depression, anxiety, general psychological distress, suicidal ideation, and suicide attempts. Despite these troubling disparities, many TGNC individuals report hesitance to seek mental health services due to concerns regarding culturally insensitive or even overtly discriminatory services from providers. In addition to decreasing service utilization among TGNC populations, discriminatory services impair intervention effectiveness even when TGNC individuals persist in seeking mental health services. The American Psychological Association (APA) and the World Professional Association for Transgender Health (WPATH) provide guidelines for culturally competent work with TGNC clients; however, research indicates a profound lack of TGNC-specific training and resources among mental health care providers. To address this gap, the present investigation utilized a mixed-method design to assess training experiences, understanding of terminology, and TGNC competence among mental health care providers at various training levels. Participants were current mental health clinicians across the United States. Implications for improving reported and demonstrated weaknesses are discussed.