A Master of Science in Nursing (MSN) is a graduate degree sandwiched between the BSN and the Doctor of Nursing Practice (DNP). Typically requiring a two to three year commitment, master s degree in nursing programs are the professional nurse s gateway to career development. It is the first step in the credentialing process required for specialized professional practice, including Advanced Practice Nurses and Nurse Practitioners. An MSN also prepares students to earn their doctorate, the terminal degree in the field.