Palliative care (derived from the Latin root palliare, or "to cloak") is an interdisciplinary medical care giving approach aimed at optimizing quality of life and mitigating suffering among people with serious, complex illness. Within the published literature, many definitions of palliative care exist; most notably, the World Health Organization describes palliative care as "an approach that improves the quality of life of patients and their families facing the problems associated with life-threatening illness, through the prevention and relief of suffering by means of early identification and impeccable assessment and treatment of pain and other problems, physical, psychosocial, and spiritual." In the past, palliative care was a disease specific approach, but today the World Health Organization takes a more broad approach, that the principles of palliative care should be applied as early as possible to any chronic and ultimately fatal illness.