This paper compares psychiatric illness in the contemporary Maori with that in the non-Maori New Zealander. The ethnic data available are all from secondary sources. The limitations of this and the problems of achieving a satisfactory definition of "a Maori" are discussed. The data suggest that the Maori have a slightly greater risk of psychiatric hospitalization than the non-Maori. First admission rates for schizophrenia are higher for the Maori, as are the readmission rates. First admission rates for major affective illness are roughly comparable in the two groups, and those for neuroses and neurotic depression are lower in the Maori. Rates of admission for alcohol abuse, alcohol dependence and personality disorders are much higher for the Maori male aged 20-40 years and this group is at greatest risk of psychiatric hospitalization. A larger proportion of Maori are admitted involuntarily, especially under the Criminal Justice Act. The median stay in hospital is not longer for the Maori but their re-admissions are more frequent. The Maori have shown an increase in first psychiatric admission rates since the 1950s, with rapid increases in the early 60s and the 80s. The rates for psychotic disorders have been relatively constant and the most significant changes have been for alcohol abuse, alcohol dependence and personality disorders. The author relates this historical change to socioeconomic and politico-cultural factors, particularly the stress of rapid urbanization.