Registered nurses suffer from depression at almost twice the rate of individuals in other professions. Major depression affects both employees and organizations. Depression is linked to increases in work absenteeism, short-term disability, and decreased productivity and presenteeism. Depression experienced by registered nurses may not be fully preventable, but realizing its presence and prevalence in the workplace is of vital importance. It is essential that we have a healthy, vibrant, and present registered nurse workforce to ensure that quality patient outcomes are achieved. This review of 36 articles assesses the current state of the science related to depression in registered nurses so that occupational health nurses can create pathways and work environments for better mental health for registered nurses.