The weighted ensemble (WE) path sampling strategy orchestrates quasi-independent parallel simulations that are run with intermittent communication to enhance sampling of rare events such as protein conformational changes, folding, and binding. Trajectories are pruned or replicated in a way that encourages sampling of under-explored regions without biasing the dynamics. I will present recent advances in both WE methodology and software along with applications to protein binding processes in the generation of pathways and calculation of rate constants.