used to predict the likely impact of changes in traffic patterns resulting from changes to traffic flow or from changes to the physical environment. Microsimulation has its greatest strength in modelling congested road networks due to its ability to simulate queueing conditions. Microsimulation models will continue to provide results at high degrees of saturation, up to the point of absolute gridlock. This capability makes these type of models very useful to analyse traffic operations in urban areas and city centers, including interchanges, roundabouts, unsignalized and signalized intersections, signal coordinated corridors, and area networks. Microsimulation also reflects even relatively small changes in the physical environment such as the narrowing of lanes or the relocation of junction stop lines. In recent years, microsimulation modelling has gained attention in its ability to visually represent predicted traffic behaviour through 3D animation, enabling laypeople such as politicians and the general public to fully appreciate the impacts of a proposed scheme. Further advances are being made in this area with the merging of microsimulation model data with cinematic quality 3D animation and with virtual reality by such companies as FORUM8 in Japan. Pedestrian or crowd microsimulation Pedestrian or agent based microsimulation has grown in use and acceptance within industry in recent years; these systems focus on the simulation of individual people moving through an area of space with respect to analytics measures such as Space Utilisation, Level of Service, Density, Packing and Frustration. Many current Traffic microsimulation software packages are combining traffic components and pedestrians to create a more complete systems while many transitional Crowd Simulation tools continue to be refined for use in large scale urban space design. Microsimulation in health sciences In health sciences microsimulation generates individual life histories. The technique is used when "stock-and-flow" type modeling of proportions (macrosimulation) of the population cannot sufficiently describe the system of interest. This type of modeling does not necessarily involve interaction between individuals (as described above) and in that case can generate individuals independently of each other, and can easily work with continuous time instead of discrete time steps. Several examples of microsimulation models in health sciences have been brought together in the U.S. National Cancer Institute's CISNET program (http://cisnet.cancer.gov/). In Canada, the Population Health Model (POHEM) is a common platform that examines multiple chronic diseases, including diabetes, cardiovascular disease and arthritis. Spatial microsimulation Economic and health approaches to microsimulation provide insight into the impacts of