A catalytic regio- and stereoselective 1,4-hydroboration of 1,3-dienes was accomplished with pinacolborane in the presence of Ni(cod)(2) and PCy3. This reaction exhibits broad substrate scope operating oil a range of Substituted dienes and Occurs with generally high levels of selectivity and efficiency. Reactivity patterns Suggest that the reactive conformation of the diene is the S-cis form. The intermediate allylboronate call be oxidized to stereodefined allylic alcohols or can be used in stereoselective carbonyl addition reactions.