The average American moves about once every 5 years. We often hear statements like this, even though they reveal little about the movement and the people involved. Actually, much of the moving about is done by a relatively small segment of the population. To illustrate, four of five Iowans counted in the 1960 census were born in Iowa. Still, this statistic sheds no light on the migration within the state. When the average person moves once each 5 years he may migrate within the state or across its boundaries. We shall examine both forms of migration in this publication, placing the major focus on movement into or out of the state.