AbstractCoefficients for the Berger formula gamma-ray buildup factor are given for ordinary, magnetite, and barytes concrete, air, sand, wood, and lithium hydride. The original data can be reproduced using these coefficients with an error for source energies greater than 2 MeV to generally less than about 5%. Errors for energies 0.5 to 2 MeV may be of the order of 20%.