How did Lenin's New Economic Policy differ from Stalin's Five-Year Plans?

Stalin instituted the Five-Year Plans in order to quickly generate capital for, and ensure the Soviet Unionâ??s economic strength in case of, another World War. One of Stalinâ??s signature moves was to reinstate state control of the farming system which had been decentralized under Leninâ??s New Economic Policy. Stalin also wished to return the Soviet economy to the policy of Bolshevism, or a nationalized, communist economy which had been eroded under Lenin's NEP.