Acyclic stereocontrol is a pressing concern in modern organic synthesis. In recent years a number of methods have been developed for the stereocontrolled synthesis of acyclic compounds. We have found two new methods for acyclic stereocontrol via (1) Lewis acid promoted reactions and (2) an electron transfer process. (1) The reaction of group 14 organometallic compounds in the presence of Lewis acid proceeds with very high and novel stereoselectivities, which can not be realized by using ordinary carbanionic species themselves. (2) The opposite diastereoselectivity is observed between one electron transfer and two electron transfer process. For example, Michael nucleophilic addition of RCuLn to γ-chiral-α β-unsaturated esters produces the anti-adduct, while the electron transfer addition gives the syn-adduct.