Transportation Policy in Developed Countries has started embracing environmental and sustainability issues, above the level of lip service, only in recent years. In developing countries even lip service has hardly started. At the heart of these issues is urban traffic management and control. Traditional studies and consultants have concentrated on forecasting and facilitating the movement of "traffic" (meaning vehicles), by traffic engineering and traffic management, rather than facilitating the movement of people and goods. Only recently have such consultants moved from infrastructure supply management to demand management where public transport (on rail and road) needs heavy priority and private transport (except on environment-friendly pedal cycles) needs deterrence by physical or fiscal measures. This is especially so in countries with low incidence of car ownership where it should be easier to inhibit car use and to some extent car ownership. For the purpose of this presentation, "Mass Transit Systems" embrace underground rail, elevated rail & surface rail (whether "heavy" or "light"), bus, busway & tramway and assorted exotica. The heavier the concentrated demand, the heavier the mode with two provisos, firstly frequency of service on any route should not exceed 10 minute headways, secondly, heavy modes, especially elevated and underground, reduce accessibility and hence patronage. The latter sacrifice urban space either to pedestrians (perhaps good) or motorized traffic (bad). Planning and operation of public transport must aim at regularity, reliability, frequency, proximity, accessibility (low-floor bus and tram) and comfort with near-seamless under-cover intra or intermodal interchange. Economic analysis of public transport must give credit for its (per passenger-km) frugality in pollutive and noise emissions and urban space usage, and a compensatory credit for negative environmental harms and high spatial profligacy (hence traffic congestion) not paid for private motorized vehicles. Finally, developing countries must learn at the very start of urban growth the lessons to be learned from the consequences of disregard of all the above aspects by developed (and perhaps more so by some developing cities so far). The presentation will include examples from cities world-wide based on personal professional observation over many decades. This paper will show that there has been an inherent implied CARS FIRST transport policy over the years.