Hardbound. 1999 marks the 40th anniversary of the inception of the ISTTT symposia. It is clear that much has changed in the field of transportation in the last 40 years but in this time the ISTTT triennial symposia have remained the premier series of conferences in transportation science.Presented here are over 30 papers exploring innovative solutions to the analysis of traffic and transportation problems through use of the models, methods and analyses both existent and under development. Issues of safety, mobility, efficiency, productivity, planning and the environment are of increasing...