A method of increasing the lifetime of an ITO-free organic lighting system comprises: providing an organic lighting element having a substrate (12) bearing a set of anode electrode metal tracks (14), a conductive organic layer (16) over said metal tracks, an organic light emitting layer (18) over said conductive organic layer, and a cathode electrode layer (20) over said organic light emitting layer, wherein said metal comprises copper, and wherein said conductive organic layer comprises a doped conducting polymer, and driving the organic lighting element with a pulsed current drive. A biphasic pulse is employed having a first, on-phase with a defined current drive and a second, off-phase with a drive having a defined potential difference of zero volts across the lighting element. The anode electrode metal may have a higher work function than the cathode electrode layer. During said zero level drive portion the different work functions provide a reverse bias electric field within the organic lighting element.