Flow regimes are reported for horizontal co-current three-phase, oil/water/air pipe flow for two different diameters. In the validation of experimental method the effect of time dependent characteristics and calming lengths are outlined. Initial two phase air/water flow studies led to the development of a universal flow regime map which gave flow pattern prediction of the various regimes by using a combination of dimensionless numbers for each phase as the mapping parameters. An adaptation of the flow regime map is presented here that permits major pattern types to be predicted for both two and three phase systems.