NCHRP Research Report 1121 distills practical tools, methods, and guidelines that help transportation agencies modernize data integration, sharing, and management for planning and traffic operations. Grounded in real-world use cases—integrated corridor management, smart-city initiatives, incident response, performance management, work-zone oversight, and more—the report captures best practices and lessons learned while showcasing proof-of-concept products that tackle persistent obstacles such as incompatible data standards, data-quality gaps, and concerns over proprietary or sensitive information. Deployment assistance examples illustrate how well-designed data architectures foster collaboration among public agencies, private partners, travelers, and connected devices, leading to more informed, data-driven decisions. A companion website hosted by the National Operations Center of Excellence (https://data.transportationops.org) compiles the full set of best practices and supplemental resources.