A reduction of two detailed kinetic mechanisms for nitrogen oxidation, GRI-Mech 2.11 and Drake & Blint, is presented which uses the conserved scalar description of species transport. Profiles of C/H/O species, temperature, and scalar dissipation rate as functions of mixture fraction are required as model inputs. Reaction rate analysis of the nitrogen chemistry is used to identify steady state relationships and pare insignificant reactions. The resultant skeletal mechanism for nitrogen chemistry can be recast as a closed set of iie linear species conservation equations far NH3, HNCO, HCNO, HCN, and NO. The concentrations of nine other intermediates (HOCN, CN, NCO, NH, NH2, HNO, N, NO2, and N2O) may be obtained through steady-state relationships. Validation of the reduced mechanisms is accomplished through comparison with the parent detailed mechanisms. Of particular significance is the dominance of the reaction HCCO + NO --> HCNO + CO in NO reburn chemistry in one of the detailed mechanisms investigated (GRI-Mech 2.11) and its derived reduced mechanism.