Rate studies of the N-alkylation of lithium diphenylamide with n-butyl bromide in THF/hydrocarbon mixtures (THF = tetrahydrofuran) are described. Dramatic induction periods observed for the N-alkylation at low THF concentrations are ascribed to the intervention of reactive mixed dimers of lithium diphenylamide and lithium bromide. In the presence of 1 .O equiv of added lithium bromide, the alkylation rate exhibits a first-order dependence on both the mixed aggregate and n-butyl bromide concentrations, supporting a pathway involving direct mixed aggregate alkylation. Incremental changes in the THF concentration uncovered contributions from several additional species. Regions of first or higher order followed by zero-order dependence on the THF concentration are interpreted as an equilibrium shift to a more reactive, highly solvated species assigned as a monomer (or ion pair). At elevated THF concentrations, the alkylation rate increases sharply as a function of the THF concentration, indicating the contribution of an additional, highly solvent dependent alkylation pathway. This latter pathway exhibits fractional-order dependence on the amide concentration, approximate first order dependence on the n-butyl bromide concentration, and a seventh-order dependence on the THF concentration. Common ion rate inhibitions by lithium perchlorate and lithium tetraphenylborate, a significant dependence on dielectric effects, and the observed reaction orders implicate a mechanism involving predissociation of free lithium ions. The appearance of competitive eliminations of the n-alkyl bromides to form 1-alkenes coincides with the appearance of the free ion alkylation pathway.