Аннотация:The next-to-leading-order jet cross section is calculated for the simplified case in which there are only gluons. Numerical results of this calculation have been presented elsewhere. Here, we describe the calculational method in some detail, deriving all of the formulas that are necessary for the numerical evaluation of the cross section. The calculation is based on the matrix elements of Ellis and Sexton. In a future paper, we will extend the calculation to include quarks as well as gluons. When quarks are included, the algebraic complexity of the problem increases substantially. However, the method to be applied is essentially the same as in the gluon-only case, since there are no new singularities in the amplitudes that are not present in the gluon-only amplitudes.