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Introduction 9 could be problematic and, in some cases, was not practical, requiring a break between the new and old data. Even with the move to enterprise database systems, many datasets remain local to specific offices and personnel that are responsible for them. In part, this is the result of a need for data creators to maintain control of the data. It can also be a result of individual offices or personnel creating tools and datasets to make their work easier and not being aware that those tools and data may have broader uses or applicability. As technology has advanced, the ability to work in a distributed computing environment has enabled systems to access data from multiple sources and locations while allowing those data to remain under the control of the sourcing office. This is particularly important for data such as tax information, which is not sourced or managed by the transportation agency. Geographic Information Systems Every transportation agency makes use of some form of GIS and many agencies now maintain enterprise geospatial database systems. Use of GIS ranges from working directly with or using customized macros on GIS software such as Esri's ArcGIS, Bentley's Microstation, or Caliper's TransCAD to working with applications that are built on GIS platforms, web-based geospatial tools and applications, applications that include geospatial capabilities, or some combination of these. This use can be as simple as reviewing geospatial characteristics on Google Maps, which only requires Internet access and simple intuitive interactions, or as complex as comprehensive transportation planning or environmental impact analyses, which may require detailed under- standing of GIS software and, in some cases, programming and system integration. Many transportation agencies have implemented enterprise GISs that support distributed computing. This capability usually includes agency-established standards for data structure and metadata--the data about the data layer including accuracy, coverage, and much more. (For a full discussion of geospatial metadata, see http://www.fgdc.gov/metadata.) When this type of GIS capability is available, core geospatial datasets, such as boundaries and street centerlines, are maintained outside the right-of-way office and have attributes that have been established and populated for other agency missions. Because parcel boundaries and their corresponding information are typically not part of these other missions, a comprehensive statewide parcel dataset is not typically part of the enterprise geospatial data. This is probably the biggest challenge to incorporating GIS into the right-of-way information management system. In agencies that do not yet have an enterprise GIS, a GIS office typically exists somewhere within the agency that supports one or more activity and may have geospatial layers that can be accessed or ported over for use by the right-of-way office. In this case, those layers may or may not have standardized structures and metadata. Additional work will probably be required to incorporate multiple layers of geospatial information that are not standardized. As with agencies that have enterprise systems, you will rarely find a parcel layer inside the agency. Even if you do not initially plan to include geospatial capabilities in your right-of-way system, it is probably worth the effort to include the architecture for a parcel layer and the necessary attributes for incorporation at a later stage of development. Appendix B includes a section on how this can be done. Implementing Geospatial Enablement Using geospatial information to inform everything from specifying where traffic is backed up to identifying the best place to locate a new highway has moved from the back offices of GIS specialists to anyone who has access to a computing device. Because the public has ready