Web-based geographic information system (GIS) technology, or web-based GIS, offers many opportunities for public planners and Extension educators who have limited GIS backgrounds or resources. However, investigation of its use in planning has been limited. The study described here examined the use of web-based GIS by public planning agencies. A 2013 web-based survey of 274 public planning agency staff throughout Wisconsin revealed that use of web-based GIS for planning tasks lags behind use of software-based GIS and that agency use is hampered by a number of barriers. The findings suggest that Extension professionals can help practitioners become more familiar and proficient with web-based GIS applications.