The ProPred-I is an on-line service for identifying the MHC Class-I binding regions in antigens. It implements matrices for 47 MHC Class-I alleles, proteasomal and immunoproteasomal models. The main aim of this server is to help users in identifying the promiscuous regions. Please cite "Singh, H. and Raghava, G. P. S. (2003) ProPred1: Prediction of promiscuous MHC class-I binding sites. Bioinformatics (In Press)" if you use this server in your research. A similar server for MHC Class-II molecules (ProPred: Singh and Raghava, 2001) is available here. For a detailed description, please refer to help page.