Reservoir fluids have been observed to show significant variations in their ability to form hydrate plugs. It is therefore likely that the different oils contains components that effect their tendency to form plugs. A procedure for evaluation of the plugging potential and for identification and extraction of naturally hydrate inhibiting components in crude oils is presented. The actual oil is characterized with respect to emulgating properties, content of polar components (resins and asphaltenes), interfacial tension, hydrate equilibrium, kinetics and potential of plug formation. The oil is then modified, by extracting the polar components. The modified oil is characterized, in the same manner as described above. The extracted polar components are used as a base for secondary extraction and fractionation of surface active components. Component fractions having high surface activity will be tested as hydrate inhibitors. The results indicate that it is possible to identify naturally inhibiting components in crude oils having a low potential of forming hydrate plugs.