Recent developments in urban storm drainage are reviewed starting with rainfall/runoff processes, followed by discussions of combined sewage, drainage impacts on receiving waters, impact mitigation, hydroinformatics, regulatory programs and conclusions. The most promising trends in this field include improvements in spatial definition of rainfall data, runoff modelling with a limited number of model parameters and recognition of modelling uncertainties, analytical statistical modelling of runoff quality, advances in the understanding and modelling of sewer sediment transport, the use of biomonitoring and modelling in assessing drainage impacts on receiving waters, further refinement of best management practices for stormwater management, development of new processes for treatment of stormwater, experience with vortex combined sewer overflow structures and their applications in combination with other treatment devices, real time control of sewer system operation, advances in hydroinformatics leading to improvements in the integrated management and modelling of drainage systems, interfacing of drainage models with geographic information systems, and improved regulation of drainage effluents.