The mechanism and kinetics of the reaction between aqueous solutions of CO a and the alkanolamines 1-amino-2-propanol, 3-amino-1-propanol,2-methyl aminoethanol and a-ethyl aminoethanol were investigated using a stopped flow technique. It was found that the reaction orders according to power law kinetics were between 1.1 and 2.0, depending on the alkanolamine and the concentration ranges investigated. This fractional order was therefore considered to be further evidence that carbamate formation takes place according to a zwitterion mechanism rather than a one-step reaction. The kinetic rate parameters for these alkanolamines were evaluated from experimental data at 303 K according to this mechanism.