Healthcare workers experience moral injury (MI), a violation of their moral code due to circumstances beyond their control. MI threatens the healthcare workforce in all settings and leads to medical errors, depression/anxiety, and personal and occupational dysfunction, significantly affecting job satisfaction and retention. This article aims to differentiate concepts and define causes surrounding MI in healthcare. A narrative literature review was performed using SCOPUS, CINAHL, and PubMed for peer-reviewed journal articles published in English between 2017 and 2023. Search terms included “moral injury” and “moral distress,” identifying 249 records. While individual risk factors predispose healthcare workers to MI, root causes stem from healthcare systems. Accumulation of moral stressors and potentially morally injurious events (PMIEs) (from administrative burden, institutional betrayal, lack of autonomy, corporatization of healthcare, and inadequate resources) result in MI. Individuals with MI develop moral resilience or residue, leading to burnout, job abandonment, and post-traumatic stress. Healthcare institutions should focus on administrative and climate interventions to prevent and address MI. Management should ensure autonomy, provide tangible support, reduce administrative burden, advocate for diversity of clinical healthcare roles in positions of interdisciplinary leadership, and communicate effectively. Strategies also exist for individuals to increase moral resilience, reducing the impact of moral stressors and PMIEs.