The composition of a rovibrational wave packet in the E((1) Sigma(g)(+)) state of Li-2 is controlled using a combination of intermediate state selection and femtosecond optical pulse shaping techniques. Intermediate state selection is accomplished using a cw laser to prepare a steady state population of a single rovibrational level in the A((1) Sigma(u)(+)) state of Li-2, which acts as the initial state for subsequent ultrafast pump/probe studies in the ''shelf'' region of the E((1) Sigma(g)(+)) state, An initial set of relative amplitudes of the wave packet eigenstates is defined by the intermediate level. Femtosecond optical pulse shaping, performed using a grating pair and a mechanical amplitude mask, is then used to further alter the wave packet composition. Quantitative changes in the Fourier transform of the pump/probe transient demonstrate that combining these two techniques can be a facile approach to manipulating wave packet composition, with the ultimate goal of controlling wave packet evolution into a desired final form. (C) 1997 American Institute of Physics.