Starting from monomethoxypoly(ethylene glycol) succinimido carbonate (2), an efficient two step synthesis of N epsilon-monomethoxypoly(ethylene glycol)carbonyl-L-lysine hydrochloride (8) is described. The hydrochloride salt 8 was used to prepare N alpha,N epsilon-bis(monomethoxypoly(ethylene glycol)carbonyl)-L-lysine (9). This is the first reported example of the synthesis of a chiral lysine PEG precursor to an active pegylated reagent.