Ad-hoc wireless communication among hi ghly dyna mic, mobile node s in a urba n network is a critical capability for a wide range of important applications including automated vehicles, real-time traffic monitoring, a nd ba ttleground c ommunication. W hen evaluating application pe rform ance through simulation, a realistic mobility model for ve hicular ad-hoc networks (VANETs) is critical for a ccurate results. This technical report discusses the implementation of S TRAW, a new mobility model for VANETs in which node s move according to a realistic vehicular traffic model on roa ds defined by re al street map data. The challenge is to create a traffic model that accounts for i ndividual vehicle motion without incurring significant overhead relative to the cost of pe rform ing the wireless network simulation. W e identify essential and opt ional techniques for m odeling ve hicular motion that can be integrated into any w ireless network s imulator. W e then detail choices we made in implementing STRAW.