We describe the achromatization of Wollaston prisms to reduce the angular dispersion in the splitting angle. Analytical theory and ray-tracing modeling is presented. In an example application, a sixfold reduction in dispersion is achieved for wavelengths in the region 400nm to 1:7µm. Experimental proof of concept is demonstrated, and in an example application, the spectral dispersion of extended images recorded through cascaded Wollaston prisms is shown to be reduced by an order of magnitude. © 2011 Optical Society of America.