Trajectories are used to study the dynamics of Li+ + (CH3)2O association. The criterion for association in the trajectories is the formation of a long-lived vibrationally/rotationally excited Li+ [(CH3)2O]* association complex with multiple inner turning points in the Li+ + (CH3)2O relative distance. Primary association cross sections are determined as a function of the initial relative translational, rotational and vibrational energy. Increasing either the vibrational or rotational energy decreases the association cross sections. Quasiclassical trajectories, which initiate (CH3)2O with zero-point vibrational energy, give thermal rate constants which approximately 50% smaller than those for trajectories initiated with no vibrational energy. The trajectory rate constants for Li+ (CH3)2O association are smaller than those calculated from canonical variational transition state theory. This difference results in part from a dynamical recrossing of the transition state in the trajectories. A bottleneck appears to be present for intramolecular vibrational energy transfer from Li+ + (CH3)2O relative translation to (CH3)2O internal rotation and vibration degrees of freedom. A comparison of trajectory, transition state theory and adiabatic capture theory methods for calculating association rate constants is given.