Drug substance development is continuous troubleshooting and risk management. With solid state chemistry you manage a drug's physchem properties by finding the polymorph that will give the perfect balance between stability, solubility and permeability. In this webinar Edwin Aret will talk about how to obtain this balance. He will especially highlight the polymorph screening process and how to optimize the crystallization. Controlled crystallization is the preferred isolation method to obtain purified material of a specific polymorphic form and crystal habit. The systematical exploration of the experimental space will identify new crystalline (salt) forms, select the kinetically accessible and thermodynamically most stable polymorph.