Seer, forecaster, prophet, geomancer, or tout - all predict future events as physicians must. The medical activity is prognosis from the Greek pro (forward) and gnosis (special knowledgeL thus foreknowledge, and the practitioner is the prognosticator, a sobriquet which falls unhappily upon the ear. Like it or not, there is nothing more critical in the management of chronic rheumatic conditions than a reasonably clear picture of what time and disease will bring. The knowledge is so much a part of ordinary medical thinking that we rarely grace it with the label prognosis. But, like so much of "ordinary medical thinking" (an oxymoron, perhaps), quantitative data are very thin and the chestnuts of personal observation and authority figure assertion loom large. Unlike several books I have seen or written, this one on prognosis needs no justification. The entirety of a person's life contributes to and confounds what the future holds. The ingredients include education levet income, support structures such as family, housing, occupation, availability of medical services, diagnosis, treatment, rate of disease progression, age, gender, race, marital status, and others too numerous to mention or too arcane to be recognized. One would think the task of estimating prognosis impossible. And yet there is light on the horizon -we do know a few things such as the effect of high rheumatoid factor titers on the prognosis of RA or the likely outcome of certain kidney lesions in SLE.