The development is described of a new molecular-mechanics procedure which is designed for investigation of the molecular structure and for the prediction of minimum-energy conformations of flexible saccharide systems. In place of the optimization of energy with respect to the Cartesian coordinates ofthe atoms, used in conventional molecular mechanics, the minimization is carried out on'internal geometrical parameters, namely, bond lengths, bond angles, and torsional angles. For this purpose, the non-derivative method of conjugate direction based on the Powell-Zangwill algorithm is used, resulting in a considerable computational advantage for large systems. Another principal feature of the procedure is the algorithm for a determination of the energetically favored orientations of pendant groups, based on a random-walk technique in a given conformation, independent of the initial starting geometry. The performance of the program RAMM using this procedure has been illustrated by comparing (~0, w) maps obtained with different approaches utilizing the MM2 set of potential functions for a model disaccharide. It is shown that the shape of the (9, v) maps and the relative energies of conformers are si~ifi~ntly affected by orientation of Pendant groups.