Contrary to the widespread perception that the‘spiritual dimension’of health isprimarily related to palliative care and has emerged relatively recently within theWHO, we show in this book that its history is considerably longer and morecomplex. The emergence of a‘spiritual dimension’in WHO discourse wasconnected to aspirations for universal primary healthcare, attempts to delivera more holistic form of healthcare, and the search for a shared ethical frame-work to unify the disparate national interests represented in the organization.Since the WHO’s birth, these themes have enjoyed sustained attention fromlargely unconnected proponents ranging from individuals to Member States,regional offices, and directors-general, all of whom have grappled with the ques-tion of what a‘spiritual dimension’of health looks like, and how it might enrichthe health policies advocated by the WHO. While ethical ideals silently motivatedmany key actors and policies—some of which, such as the provision of universalprimary healthcare, embody the organization’s loftiest aspirations—the WHO’sofficial relationship with‘spirituality’advanced infits, leaps, and setbacks. At timescreative and interdisciplinary, at others deeply political, this process was marked bycycles of what we term‘institutional forgetting’and‘remembering’. Rather than asa triumph of religious lobbyists, we argue, the‘spiritual dimension’of health maybe better understood as a‘ghost’(or‘spirit’) that has haunted—and continues tohaunt—the WHO as it comes to terms with its constitutional mandate to advancehealth as a state of‘complete well-being’available to all.