Is a recently designated semi-disease, often attributed to EBV (the Epstein-Barr virus) or CMV (Cytomegalovirus) infections, characterised by FUOs (Fevers of Unknown Origin) and resulting in the patient suffering FLS (Feels Like Shit). In most of us, the microorganisms involved in CFS usually provoke nothing more than a head cold; in some individuals, however, they induce a long, grinding, and debilitating disorder, characterised by exhaustion, depression, periodic fevers...a crazy-quilt of symptoms that frustrates both the sufferer and the sometimes sceptical physician. MCS (Multiple Chemical Sensitivities) are another syndrome that is often lumped with CFS, and they may often be two faces of the same condition. I am not using all these acronyms to mock the conditions, but as an irony. There is too much (Acronym Safety Syndrome) in medicine, reducing complex and frustrating conditions to insider's techno-babble, somehow therein trivialising otherwise complex, painful and crazy-making problems. The widest use of acronyms (AIDS, HIV, CFS, MCS, MS etc.) seems to be for diseases hardest to treat, least responsive to procedural medicine, and most depressing to discuss with patients or survivors.