Abstract The Large Electron Positron collider LEP at CERN was commissioned in 1989 and finished operation in November 2000. During this period it was operated in different modes, with different optics, at different energies, and with varied performance. In the end, LEP surpassed all relevant design parameters. It has provided a large amount of data for the precision study of the standard model, first on the Z 0 resonance, and then above the W ± pair threshold. Finally, with beam energies above 100 GeV, a tantalizing glimpse of what might have been the Higgs boson was observed. A brief history of the main modes of operation, associated performance, the highlights and the challenges met over the 12 years of running is presented.