A method and system for dehydration of a gas phase and hydrate inhibition of a liquid hydrocarbon phase in a multiphase hydrocarbon fluid stream containing water. The method may include (i) separating the hydrocarbon fluid stream into a liquid phase and a first gas phase, (ii) adding hydrate inhibitor to the first gas phase, and (iii) separating off condensed liquids and a second gas phase. The first gas phase has a water dew point that is lower than the initial multiphase hydrocarbon fluid stream and the second gas phase has a lower water dew point than the first gas phase. The hydrate inhibitor has a water content that is low enough to enable it to dry the first gas phase, the hydrate inhibitor being separated off with the condensed liquids and mixed with a part or all of the liquid phase from the separation to inhibit the liquid phase.