Copolyesters comprising monomeric units derived from norbornane compounds such as 2,3-norbornane dicarboxylic acid anhydride or dicarboxylate exhibit amorphous characteristics. Exemplary copolymers are obtained by polycondensation of ethylene glycol, terephthalic acid, and up to about 40 mole % cis-norbornane-endo-2,3-dicarboxylic acid anhydride or dimethyl trans-norbornane 2,3-dicarboxylate or mixtures thereof, based upon the total moles of ester forming components of the polyester. The copolymers containing monomeric units derived from norbornane dicarboxylic acid or dicarboxylate can be obtained by melt polymerization and exhibit no or very low crystallinity. The copolyesters may be used to produce transparent, optically clear amorphous articles of manufacture such as containers, extruded objects, and packaging by melt processing techniques such as injection molding, blow molding, extrusion or thermoforming.