Pilot plants are traditionally recognized as a tool for scaling-up a process from the laboratory bench studies to a commercial plant operation. Pilot plants are also generally recognized as economic method for troubleshooting existing commercial processes that are not performing as well as one would expect. Shell designed, constructed and operated a pilot plant copying the Shell Higher Olefin Process-Alpha Olefin (AO) Units. Shell's Alpha Olefins units, three units operating globally at the time, had been in operation for more than fifteen years. The AO pilot plant was used not for scale-up or troubleshooting, but rather for data generation to support development of a computer model of the AO process. This paper describes the difficulty we had in scaling-down a commercially practiced process, the trials and tribulations of running the pilot plant and the question of the validity of the data generated for the model.