Quality and safety of nursing practices are major concerns in healthcare settings. This study adds to the body of evidence on nursing competency and safe nursing practice. The purpose of the mixed method study was to test the theory that nursing competence impacts the quality and safety of nursing practices in the multicultural healthcare environment in the Kingdom of Saudi Arabia. The descriptive quantitative study aimed to determine competency levels of participant nurses using selected nursing core competencies. The grounded theory qualitative study explored if a structured nursing competency program can help Nurse Educators and Managers improve nursing competence in the delivery of quality and safe nursing practices. The finding results of this mixed method study have proven that the structured Nursing Competency Program has the potential to assess, maintain, monitor, and improve the nursing competence. The research study has validated the potential of a hospital based competency program to influence quality and safety of nursing practices in the selected population in the Kingdom of Saudi Arabia.