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You may be interested in a new report by the Australian Bureau of Transport Economics, URBAN TRANSPORT MODELS: A REVIEW, Working Paper 39. It is available for free by email ([log in to unmask]) or website (www.dot.gov.au/programs/bte/bethome.htm). The report includes a comparative analysis of various transport models covering four major categories: four-step, behavioral travel demand, linked urban land use-transport models, and integrated urban land use-transportation models. It finds that each type has strengths and weaknesses. The analysis concludes that integrated land use-transport models incorporating behavioral relationships are most accurate. It seems to be an good overview of available models. I am rather less impressed by another Bureau report, FORECASTING LIGHT VEHICLE TRAFFIC, Working Paper 38, which uses a simple model to predict future vehicle travel and congestion based on population, vehicle ownership, per vehicle annual VKT trends. It fails to include any pricing factors (what if fuel prices increase in real terms in the future?), congestion (urban roads tend to achieve a self-limiting equilibrium as congestion increases), or TDM measures (per-capita vehicle travel varies significantly depending on a variety of local land use, pricing, and travel choice factors). There is a danger that such models create self-fulfilling prophecies by predicting vehicle travel growth which is used to justify increased road capacity, which leads to increased vehicle travel. Sincerely, Todd Litman, Director Victoria Transport Policy Institute "Efficiency - Equity - Clarity" 1250 Rudlin Street Victoria, BC, V8V 3R7, Canada Phone & Fax: 250-360-1560 E-mail: [log in to unmask] Website: www.islandnet.com/~litman %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%