1,3-Dipolar cycloadditions of nitrile oxides with unsymmetrically substituted norbornenes were investigated. The cycloadditions were found to be completely stereoselective, giving only the exo cycloadducts in moderate to good yields. Regioselectivities in the cycloadditions ranging from 50:50 to 100:0 were observed with various unsymmetrically substituted norbornenes.