This is a descriptive study of Iowa's population. Data are from secondary sources, mainly from census and vital statistics records. The 1970 United States Census revealed a total population of 2,824,376 persons in Iowa, slightly larger than that of 1960 (2,757,537). Iowa is one of the states with slowest population growth. The net population gain in 1960-1970 was 66,839 persons, only about one-fourth of the excess of births over deaths. The state ranked 44th in percentage of population gain, although 25th in population in 1970. Iowa was predominantly rural up to 1950, but had become more than 50 percent urban by 1960, trailing the national average by 10 to 15 percent in proportion of urban population.