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Droughts are governed by regional climatic parameters. The ratio of mean annual precipitation (P-a) to global terrestrial mean annual precipitation (P-g), and the ratio of mean annual potential evapotranspiration (E-p) to mean annual precipitation (P-a) have been used to define the climatic regions. The relationship of average drought frequency with the evapotranspiration/precipitation ratio (E-p/P-a) and the ratio of mean annual deficit to mean annual precipitation, (E-p - P-a)/P-a, are derived for arid, semiarid and subhumid climatic regions in India. The average annual drought frequency is found to decrease gradually from dry to wet regions. The return period varies from two to three years in arid regions (12 > E-p/P-a greater than or equal to 5), three to five years in semiarid regions (5 > E-p/P-a greater than or equal to 2), and five to eight years in subhumid regions (2 > E-p/P-a greater than or equal to 3/4). The results are compared with drought experiences in other countries. These relationships may be useful for critical analysis of drought and for planning of drought management strategies in a given region.