[en] The use of quantum chromodynamics perturbation theory on large momentum transfer hadronic processes is examined. A self-consistent computational algorithm based upon Feynman diagrams is considered. Deep inelastic leptoproduction is discussed as an example of the QCD hard process and structure functions are calculated to all orders in the renormalized coupling constant in the leading logarithmic approximation. Explicit diagram-by-diagram calculations are exhibited through O(g⁴) and then extended to all orders through isolation and detailed analysis of the diagrams contributing leading logarithms. (U.K.)