Background: Nursing regulation is a key component of health system governance; however, its role in structuring the development and deployment of professional competencies remains insufficiently examined, particularly in emerging health systems. Objective: To map and synthesize the evidence on nursing regulation and its relationship with professional competencies across the nursing profession, including the development of advanced nursing roles, and to analyze the Mexican regulatory framework within an international context. Methods: A scoping review was conducted using a structured and transparent approach. Searches in Scopus, Web of Science, and PubMed identified 194 records. After duplicate removal and screening, 17 studies met inclusion criteria based on relevance to regulation, scope of practice, and competency development. In parallel, 13 regulatory instruments in Mexico were identified through targeted searches of official sources; 9 key documents were selected based on specificity and relevance. Data were analyzed using a policy-oriented framework. Results: Regulatory frameworks consistently define scope of practice and enable the translation of competency-based education into recognized clinical roles. Regulatory coherence was associated with expanded professional autonomy, advanced role development, and improved workforce integration. Fragmented regulatory environments were linked to misalignment between education and practice and underutilization of competencies. In Mexico, a broad but fragmented regulatory architecture was identified, lacking a unified regulatory axis and an autonomous professional body. Conclusions: Nursing regulation functions as a structural determinant of professional competency deployment. Strengthening regulatory coherence is essential to align education, practice, and health system needs, with implications for workforce performance, patient safety, and system sustainability.