Introduction: The focus of clinical mentoring in nursing specialists is to develop both generic or transversal skills, as well as specific skills needed to assess their profile and become a graduate student under the guidance of experts. Objective: The objective of this study is to diagnose the transversal competencies of clinical mentors from the Unique Program of Nursery Specialties (UPNS) in student body training. Method: This study utilized a descriptive and phenomenological interpretative approach. Twelve informants from UPNS participated, and the variables were clinical mentoring and transversal competencies from novice and senior mentors. Two focus groups were conducted for data collection, and data analysis was performed according to Strauss and Corbin. All participants provided signed informed consent. Results: Post-analysis of qualitative data revealed three categories with subcategories. Category 1: Strengths of clinical mentors in three dimensions. Sub-categories: 1.1) PD: Academic and personal companionship; 1.2) PD: Guidance with humanist focus and feedback from mentor to student in real scenarios; 1.3) PD: Guidance in the teaching-learning process; 1.4) DD: Integration of theoretical-practical knowledge and development of advanced abilities in nursing for clinical practice; 1.5) CD: Responsibility and commitment from student's characteristics to group's general statements. Category 2: Competencies that lead the clinical mentor in pedagogy, discipline and generic dimensions, reported 9 subcategories six of them focused on the didactics of clinical mentors, and three on the interpersonal communication between mentors. Category 3: Opportunity areas to develop by the clinical mentor. From a mentor's perspective, eight subcategories revealed transversal competencies that define a clinical mentor for UPNS. In this state, competencies are oriented toward the pedagogical and interpersonal communication dimensions, but central aspects are recognized between disciplines, namely,