A detailed study has been made of the transient species produced by the reaction of e–aq, H and OH radicals with acrylamide(m1) in aqueous solution at natural pH (6) and at pH = 11, using the technique of pulse radiolysis. The intense transient absorption spectrum which was observed at natural pH has been assigned to the protonated monomer radical anion, ·m1H, and the products Rm1·, of the reaction of R (= H, OH) with monomer. Their decays are second order and values of the extinction coefficients and rate constants have been determined. The yields of ·m1 H and Rm·1 as a function of [m1] have been obtained and are compared with other solute systems which scavenge e–aq in spurs. Thin layer chromatography has been used to identify adipamide and pionamide as two of the seven products obtained from pulse-irradiated solutions of acrylamide and an estimate of the total product yield has been made on the basis of these results. At pH = 11 the transient absorption spectrum has been assigned to the monomer radical anion, ·m–1 and Rm1·; the decay of the former was first order whereas that of Rm1· was complex and occurred with the concomitant growth of a permanent species. The extinction coefficients and rate constants for the decay of ·m–1 and Rm1· have been determined. The yields of ·m–1 and Rm1· as a function of [m1] have been obtained and compared with the corresponding yields of ·m1H and Rm1· at natural pH. Absolute rate constants (M–1 s–1) have been obtained for the reaction of acrylamide with H atoms, (1.8 ± 0.2 )× 1010, CO–2·, 4 × 107, and ·m1H, (2.5 ± 0.4)× 105, for reaction of ·m1H with Ag+, (1.1 ± 0.4 )× 108, and for reaction of e–aq with propionamide, (3.0 ± 0.5)× 107, α-chloropropionamide, (5.8 ± 0.5)× 109, and β-chloropropionamide, (1.8 ± 0.2)× 109. E.s.r. spectra in α-methyl tetrahydrofuran glass at 77°K have been obtained for the radicals ĊH2CH2CONH2, CH3ĊHCONH2 and the electron adduct of acrylamide. The yield and decay data presented in a previous publication for pulse radiolysed aqueous solutions of methacrylamide, N-t-butylacrylamide, acrylonitrile and acrylic acid have been recalculated in view of the yield dependence of (Gε)·m1H275 and (Gε)Rm1·370 observed for acrylamide.