Mixed-use neighborhoods, which feature increased housing/job variety and density, can create pedestrian and bicycle-friendly environments by reducing dependency on vehicles and traffic congestion, and shortening distances between housing, workplaces and other destinations. Municipal regulations are vital to modern mixed-use developments due to their capability to control the direction of metropolitan growth. In this research, I have attempted to make a correlation between local regulations and current neighborhood development patterns in three well known, mixed-use neighborhoods using the case study approach. Three mixed-use neighborhoods, the North Pearl District (NPD; Portland, Oregon), South Lake Union (SLU; Seattle, Washington) and False Creek North (FCN; Vancouver, Canada), were chosen for this case study research. I examined and visualized the local regulations that pertain to mixed-use development of each neighborhood using Illustrator and SketchUp. I also analyzed and discussed U.S. Census information, including households per acre, average household size and household vehicle occupancy. The investigation indicates that among the three neighborhoods, the mixed-use regulations of FCN are the most straightforward and clear. This is reflected in the consistency between regulations and current land uses. The overall mixed degree in NPD is relatively large likely due to its incentive regulations, making itself as a highly walkable neighborhood. The local regulations in SLU are the most complicated, and focus on attracting innovative firms. In conclusion, we have conducted a study to investigate the development of mixed-use neighborhoods by scrutinizing local regulations and analyzing current situations and statistical data. The results indicated that the straightforward and incentive regulations, such as legalized neighborhood land use plan and bonus floor area ratios, benefit the mixed-use developments of neighborhoods by increasing the efficiency in land use and maximizing the mixed-use degree, thus leading to a compact, walkable and vital community. / text