Cyclization of (alkoxycarbonyl)methyl radicals generated from bromoacetates proceeds in the 8-endo mode to generate heptanolactones. Three distinct types of 8-endo/5-exo tandem radical cyclizations produce different bicyclic heptanolactones. In certain cases, intramolecular free-radical attack on the heptanolactone carbonyl group initiates further skeletal rearrangement. Ab initio calculations indicate that the preference of the 8-endo cyclization over the 5-exo mode originates from the conformational bias of (allcoxycarbonyl)methyl radicals favoring the Z- over the E-conformation.