Proportions of 2000 Oregon teachers surviving in their respective school districts in five successive years approximated a negative exponential function. The slope of this survival curve was strongly affected by three attributes: sex, age at employment (females only), and school district size (males only). Comparisons of data obtained at different times and places revealed substantial similarities in curve slopes when the three attributes were controlled, except in the case of data covering World War II. A theoretical model of forces affecting teacher survival was proposed.