Measured values of turbulence intensity for annular gas/liquid flow are examined and contrasted with values from gas/solids how. It is suggested that the larger values (relative to gas only values) found in gas/liquid how are due to two contributions: the rough interface of the wall film and drops which are slow moving just after their creation from the wall film. A significant portion of these have Reynolds numbers >400 and, therefore, contribute to turbulence production unlike equivalent but faster moving particles in gas/solids flow.