Two critically important areas of research are the long-term course of illness and predictors of outcome in chronic schizophrenia. Although these two areas have been actively investigated throughout the 20th century, there is still a lack of agreement about even basic features of the long-term outcome of schizophrenia as well as a lack of validating evidence for putative predictors of outcome. Determining the long-term outcome of schizophrenia has implications for the pathophysiology and public health policy of this illness. For example, a course of illness that is marked by progressive deterioration may suggest a degenerative disease process, whereas a course that remains stable or improves over time may be more consistent with non-degenerative hypotheses such as neurodevelopmental, infectious, or toxic processes. In terms of public health policy, the allocation of resources related to issues such as community-based versus hospital-based care will be heavily influenced by knowledge of the level of chronicity and impairment associated with schizophrenia throughout the lifetime of affected individuals. Validation of predictors of outcome will have immediate clinical relevance, as well as providing support for pathophysiological hypotheses.