On the basis of historical trends and current estimates, short-run demographic projections were made for India. This was done for 2 reasons: the working hypotheses for future trends are less likely to be fallible if the future estimates are made within the "focal length" of the base data. Secondly, a short-run projection synchronizing with a short term development plan, such as 5-year plans adopted by India, is more illuminating than projection for a distant future. A short-run projection of population provides a general framework for further projection at a later date when more demographically relevant information is available. For present purposes, the administrative divisions as existed at Census 1971 were adopted. The takeoff point of the projection was March 1, 1971. The state level estimates of population also were made to get disaggregated estimates as well as the sectoral growth patterns of the country. The usual graduation methods of adjustment of the base population at Census 1971 were unsatisfactory so a mathematical model was evolved to generate an approximately corrected age structure. The 1971, 1981, and 1986 population was estimated under consistent sets of estimated values of the components of growth. The estimates could be improved by iteration and the algebra underlying the techniques, developed and made more precise. The vital rate estimates of the Sample Registration Scheme (SRS) were accepted as the 1st approximation for subsequent improvement. The birth and death rates estimated from the SRS are 36.9 and 14.9 respectively in 1971. Gross underenumeration is indicated and consistency criteria are used to improve the estimates. There are clear indications that the birthrate, assumed to be invariant thus far, had begun declining after 1971. The experience of the SRS confirmed such a trend for the 1971-75 period. A negative exponential was fitted to the time series of adjusted birthrates in 1971, 1972, and 1975. According to the projection, the proportion of the aggregate population below age 15 is expected to decline from 43.3% in 1971 (41.0% in 1981) to 37.7% in 1991. Under the assumed future course, the moderate fall in fertility makes its effect felt in the preadult age range. On the other hand, the proportion of working age (15-59) population will increase by a little over 5 points during the 20 years. The proportion of old age (60+) population, which would increase by about 19 million from 1971-91 as per the projection, is likely to follow the same trend, mostly due to the decline in fertility.