There is compelling evidence that humanitarian staff and volunteers face an increased risk of adverse mental health conditions due to their work, including anxiety, depression, post-traumatic stress disorder, and burn-out. This article first outlines the mental health consequences associated with working in the humanitarian sector, linking these outcomes to contextual, operational and organizational psychosocial risk factors. Building on both the evidence available and the theoretical models in mental health at the workplace, and going beyond solely offering psychosocial support interventions, we propose an evidence-based framework to guide protective actions at the individual, group, leader, organizational and overarching contextual levels (the IGLOO model), tailored to the specific challenges of humanitarian contexts. Based on our experience with the International Committee of the Red Cross, we present two examples of utilizing this framework within two interventions: (1) training managers to strengthen practices that promote and protect well-being, address psychosocial risk factors, identify individuals showing signs of distress and facilitate safe access to psychological support, and (2) applying a psychosocial response framework to support staff following critical incidents. Finally, we discuss the advantages and challenges of adopting an integrated psychosocial approach to staff care, drawing implications for policy and practice from our interventions and broader experience within the sector. We conclude that humanitarian organizations should adopt an integrated approach to duty of care, prioritizing not only treatment but also the prevention and mitigation of psychological harm among staff and volunteers operating in conflict zones, extending beyond immediate crisis support to ensure sustainable protection of mental health.