Environmental exposures may increase the risk of many chronic diseases, either directly, or through their interaction with individual characteristics such as hormonal status, immune response, or genetic susceptibility. There are a number of chronic diseases with poorly understood etiologies that are likely to have an environmental component. Similarly, a wide range of exposures that have been studied for cancer effects have only recently been considered as likely causes of other chronic diseases. 1.) Data from a study of chronic renal disease continue to be exploited to identify additional potential risk factors. In a recent analysis, a history of kidney stones was found to increase risk for interstitial nephritis and diabetic renal disease. While it is possible that similar risk factors cause both stones and chronic kidney disease, it appears that kidney stones are an independent predictor of kidney disease after taking into account other known risk factors. This is consistent with several known mechanisms for these diseases. Other factors still being evaluated include the role of family history of kidney disease, diabetes, and hypertension, and the importance of occupational exposure to silica. Plans are being developed for a subsequent study of glomerulonephritis and occupational, familial, and lifestyle factors. 2.) Exposure to agricultural chemicals may have several untoward health consequences but previous studies have focused primarily on cancer risk. In a collaborative effort, we are assembling a cohort of 75,000 licensed pesticide applicators and their spouses. This group is being followed prospectively for cancer incidence and mortality, but data collected at enrollment are being used to explore relationships between pesticides and other exposures to reproductive, neurologic, immunologic, respiratory, and renal health. To date, data have been collected for 20,000 licensed pesticide applicators and 7000 spouses of farmer-applicators. A special effort to enhance the enrollment of minority farmers has been implemented through African American churches.