"Health professionals require support and recognition to help manage the well-known impact of critical or sentinel events relating to patient care. The potential distress can be magnified or mitigated by the response of the organization and colleagues. However, strategies that are accessible, relevant, and effective in the aftermath of a poor outcome are not well established. Using an action research methodology, a support tool was collaboratively designed, developed, and evaluated in a maternity service of one organization and adapted to the mental health and addiction service in another. Four principles that are intrinsic to the establishment of support tools became apparent across the two settings. Through applying these criteria to the customization of the support tool, it became relevant within the new service setting, and an implementation guide for other organizations was created. Although undertaken pre-pandemic, insights derived from this study may benefit post-pandemic situations where the need for health professional support is even greater."