This project will improve accessibility calculation capabilities and understanding of travel behavior by integrating data about highway bus operations, park-and-ride facilities, and urban parking costs. Each component will be analyzed individually, and then merged to develop a recommended methodology for calculating accessibility and estimating traveler mode choice in contexts where park-and-ride transit is an option. The results can be applied to better understand current accessibility conditions and travel behavior, to evaluate planning scenarios and guide project selection and prioritization, and to inform operational decisions involving park-and-ride facilities and highway transit operations. Where possible and appropriate, the accessibility metrics used in the project will incorporate measures of variation in order to reflect the reliability of different transportation modes in providing access to destinations. First, highway bus operations will be analyzed by combining GPS-based highway congestion/speed data with transit schedules and vehicle location data to estimate the accessibility impact of different highway operating environments for buses, including general-purpose lanes, bus-on-shoulder operation, and managed lanes. Second, park-and-ride (P&R) facilities will be analyzed by calculating accessibility from home location to P&R locations and from P&R locations to job locations, and then merging these into a combined home-work accessibility metric which includes the time cost of pedestrian travel within P&R lots and from the final transit stop to the destination. Third, urban parking costs will be analyzed based on locating and surveying parking lot operators to collect both daily and contract parking rates. Fourth, these three components will be combined in a "time+money" accessibility metric which reflects the cost of travel not just in time, but also includes financial costs such as transit fares, parking fees, personal vehicle operating costs, and value of time based on typical wage levels at origin locations. This accessibility metric will be combined with results from earlier and ongoing research to produce a more robust accessibility-based model of mode choice which, for the first time, includes P&R transit as a distinct mode. Finally, the project will demonstrate how these metrics and tools can be applied to hypothetical planning scenarios involving P&R facilities and highway bus operations.