Abstract: The invention provides a synergistic surfactant composition comprising: (a) from 5 to 95 wt % of a first surfactant which is selected from derivatives of alkyl polyglucosides and mixtures thereof; and (b) from 5 to 95 wt % of a second surfactant which is selected from: amphoteric surfactants, cationic surfactants, anionic surfactants, non-ionic surfactants, and mixtures thereof. This surfactant composition may be used to generate foam that is used for unloading a liquid from a hydrocarbon reservoir. It may be that the liquid unloading of foam generated using the surfactant composition is greater than that of foam generated from the first and second surfactants when they are foamed individually.