This volume contains the proceedings of the 19th International Conference on Logic Programming, ICLP 2003, which was held at the Tata Institute of F- damental Research in Mumbai, India, during 9-13 December, 2003. ICLP 2003 was colocated with the 8th Asian Computing Science Conference, ASIAN 2003, andwasfollowedbythe23rdConferenceonFoundationsofSoftwareTechnology and Theoretical Computer Science, FSTTCS 2003. The latter event was hosted by the Indian Institute of Technology in Mumbai. In addition, there were ?ve satellite workshops associated with ICLP 2003: - PPSWR 2003, Principles and Practice of Semantic Web Reasoning, 8th Dec. 2003, organized by Fran, cois Bry, Nicola Henze, and Jan Maluszynski. - COLOPS 2003, COnstraint & LOgic Programming in Security, 8th Dec. 2003, organized by Martin Leucker, Justin Pearson, Fred Spiessens, and Frank D. Valencia. - WLPE 2003, Workshop on Logic Programming Environments, organized by Alexander Serebrenik and Fred Mesnard. - CICLOPS2003,ImplementationofConstraintandLOgicProgrammingS- tems, 14th Dec. 2003, organized by Michel Ferreira and Ricardo Lopes. - SVV 2003, Software Veri?cation and Validation, 14th Dec. 2003, organized by Sandro Etalle, Supratik Mukhopadhyay, and Abhik Roychoudhury.