Labor productivity (output per hour) in the private nonfarm business sector is reported to have been rising at an annual rate of about 1 percent since 1973. At the same time, output per hour in the nonfinancial corporate sector is estimated to have been increasing at a 13/4-percent annual rate. Given that the nonfinancial corporate sector is about two-thirds of the aggregate, these statistics imply that output per hour elsewhere in private business has not increased, on average, for more than two decades. Because it seems unlikely that major sectors of the economy have failed to become more efficient over the years, it would be useful to try to identify at a more disaggregated level those segments of the economy with persistently dismal measured productivity performance. This paper presents such a disaggregation. The decompositions are by legal form of organization, with gross breaks within the corporate sector, and by detailed industry. For expository convenience, we refer to the former as the sectoral decomposition and the latter as the industry decomposition.