The chemical composition, morphology and configuration of a series of solid lactide-glycolide copolymers (PLA(X)GAy : X, % L-lactide and Y, % glycolide) were studied by solid state C-13 n.m.r., infra-red and Raman spectroscopy. Chemical composition was evaluated from the relative intensities of CH2 and CH carbon n.m.r. peaks and from the intensity ratio of delta CH2 and delta(as)CH(3) bending Raman peaks. Relationships with GA% content were compared. Raman spectroscopy appeared more sensitive to the stereochemistry of copolymers than CP/ MAS C-13 n.m.r.. It allowed discrimination of amorphous PLA(42.5)GA(15) from PLA(85)GA(15), and PLA(37.5)GA(25) from PLA(75)GA(25) based on the new band at approximate to 1334 cm(-1) assigned to delta CH bending modes relative to D-LA units. In contrast, solid state C-13 n.m.r. did not allow distinguishing the specific L- and D,L-LA unit distribution present in the terpolymers.