Title: The impact of in-silico methods on lead discovery Author: Pat Walters Vertex Abstract: Computational techniques have become an integral part of the lead discovery effort in many pharmaceutical companies. The approaches employed range from simple counting methods such as the "rule of five" to complex grid computing systems for virtual screening. In-silico methods for predicting physical properties and pharmacokinetic parameters are now being used to select screening compounds and prioritize lead series. In addition to being useful for compound selection, in-silico methods can also provide a means of organizing and rapidly interpreting screening data. The presentation will focus on the impact of in-silico techniques on lead discovery efforts at Vertex Pharmaceuticals.