Labor productivity in U.S. coal mining increased at an average annual rate of slightly over four percent during the past 45 years. This report examines key factors contributing to that record - particularly, technological innovation in both surface and underground mining and concurrent geographic shifts in U.S. coal production. Health, safety, and environmental regulations introduced in the sixties and seventies, as well as labor unrest, interrupted long-term productivity advance; but the interruption was of limited duration. Although our principal focus is on worker productivity, steady growth in the relative importance of non-labor inputs underscores the need to consider total factor productivity. The report touches on the productivity record using that measure.