All modeling processes require data. For predictive toxicology, the starting place for all models is the collation of toxicological data. This chapter will describe where toxicological data may be obtained and how they should be approached. The reader is also referred to a number of other papers where the reader may obtain further information (1,2) and the excellent collections of papers published in Toxicology, Volume 157, Issues 1-2 (3-14) and Volume 173, Issues 1-2 (15-28). It is hoped that this chapter will provide a source of information for

further investigation. It is well beyond the remit of one chapter, and probably the knowledge of one scientist, to describe all sources of information. However, it is hoped that this chapter will provide a starting place to show how data may be obtained for predictive toxicology.