We have carried out a genome-wide screen for novel N-ethyl-N-nitrosourea-induced mutations that give rise to eye and vision abnormalities in the mouse and have identified 25 inherited phenotypes that affect all parts of the eye. A combination of genetic mapping, complementation and molecular analysis revealed that 14 of these are mutations in genes previously identified to play a role in eye pathophysiology, namely Pax6, Mitf, Egfr and Pde6b. Many of the others are located in genomic regions lacking candidate genes and these define new loci. Four of the mutants display a similar phenotype of dilated pupils but do not appear to be allelic, and at least two of these are embryonic lethal when homozygous. This collection of eye mutations will be valuable for understanding gene function, for dissecting protein function and as models of human eye disease.