A method for the manipulation of crystal shape by using cycles of growth and dissolution is presented, representing a unique process-based solution to an important product quality concern. Using 3-D shape evolution models for faceted crystal growth and dissolution, results are reported for cycling both an illustrative crystal system, as well as a physical plate-like system. The results show that crystal shape can be manipulated by cycling when the relative growth and dissolution rates are anisotropic, which can be caused by differences in growth mechanism, asymmetry in super/undersaturation, and by the use of surface active additives. Since this method of crystal shape enhancement uses the existing liquid solution, it could be a valuable alternative to the traditional methods which often require changes in the chemical nature of the solution, for example, by changing solvent. (c) 2007 American Institute of Chemical Engineers