The present invention provides processes for removing organic solvent from crystals of atorvastatin hemi-calcium containing organic solvent. In one process, the organic solvent is displaced by vapor diffusion of water in a vessel maintained at elevated humidity. In a second process, the organic solvent is removed by fluidized bed drying. The present invention further provides atorvastatin hemi-calcium containing 1% or less organic solvent, which can be obtained from atorvastatin hemi-calcium that has been crystallized from an organic solvent-containing solution by practice of the processes of the invention.