JIGSAW is a program designed to use the output from gene finders, splice site prediction programs and sequence alignments to predict gene models. The program provides an automated way to take advantage of the many succsessful methods for computational gene prediction and can provide substantial improvements in accuracy over an individual gene prediction program. JIGSAW is available for all species. We have tested JIGSAW on Human, Rice (Oryza sativa), Arabidopsis thaliana, C. elegans, Brugia malayi, Cryptococcus neoformans, Entamoeba histolytica, Theileria parva, Aspergillus fumigatus, Plasmodium falciparum and Plasmodium yoelii.