Tehran Comprehensive Transportation and Traffic Studies began in 1994 with the col-lection of socioeconomic data. network characteristics, public transit data, and pertorming thp sur-veys and traffic volume counts Trip generation. trip distribution, and mode choice models were calibrated using these data regarding the size of Techran and consequently its database,and also the details aimed for in these studies, EMME/2 was selected as the appropriate software tool for demand prediction and traffic assignment. Tehran transportation modeling underwent two principle stages f a. Simdating the corent state, b. Future prediction and optimizing transportation system through defining and evaluating altematives. Following steps were taken in the transportation modeling using EMME/2; a. Thp generation forecasting, b. Thp distribution forecasting f c. Mode choice forecasting, d. Forecasting cordon thps and goods transportation; e. Combining trip mathces for each mode f. Segregating trips by modes allowed into the CBD from those by other modes.