Canada has been a leader in some aspects of psychiatric epidemiologic research. One of the earliest psychiatric epidemiologic studies was conducted here: the Stirling County Study. An area where Canada has not yet made a contribution is in studies of the Burden of Mental Illness. Burden studies go beyond estimating prevalance - how many people has a disorders - and examine how they are affected, and for how long. This week, a detailed burden of mental health report was released for the Province of Ontario. I is called "Opening Eyes, Opening Minds: The Ontario Burden of Mental Illness and Addictions Report." The report is available on-line: here . Major depression contributes to disease burden through YERFs (year-equivalents of reduced functioning) - and the total disease burden is YERFs + premature mortality (YLL, years of life lost). Major depression alone contributes more burden of disease than any type of cancer, and than all infectious diseases combined.