Background: Values are the basis of nursing practice, especially in making decisions about complicated ethical issues. Despite their key role in nursing, little information exists on the factors affecting their development and manifestation in nursing students. Objective: This study identifies and describes the facilitators and inhibitors of the development and manifestation of professional values based on the experiences of nursing students and instructors and nurses. Research design: Data were collected through 29 semi-structured interviews and two focus group interviews in 2013–2015 and were analyzed using the conventional content analysis method of Elo and Kyngäs. Participants and research context: In total, 18 nursing undergraduates, five nursing instructors, and five nurses from Shiraz University of Medical Sciences and one of the teaching hospitals in Shiraz were selected through purposive sampling. Ethical considerations: The research was approved by the Ethics Committee of Shiraz University of Medical Sciences and the teaching hospital examined. Findings: The findings consisted of two categories: personal and environmental factors. Personal factors consisted of the two subcategories of personal stimuli (work experience and past relationships, inner beliefs and acting on values, belief in God and a divine worldview) and personal inhibitors (the lack of professional motivation and enthusiasm, negative emotions). Environmental factors consisted of the two subcategories of environmental stimuli (cooperation, order and discipline) and environmental inhibitors (unfavorable work environment, society’s negative attitude toward nursing, the violation of rights). Discussion and conclusion: Given the impact of personal and environmental factors on the development and manifestation of professional values in nursing students, it is upon the education authorities to take account of them in their planning, and nursing managers are also recommended to further address these factors in their development of a proper work environment, provision of standard facilities and removal of barriers. [ABSTRACT FROM AUTHOR]