Geographic information systems aren’t exactly new. Drugstore chain Walgreens has used the technology for close to 15 years for market planning.

More recently, however, the company has endowed that visual information with location-specific data—and published far more broadly, so that store managers and its corporate real estate team can use it for planning.

The system, called WalMap, can be used to visualize local community trends. A spike in flu medication prescriptions could help store managers decide earlier to order more vaccine, preventing shortages. Walgreens sales executives can reference trends in supplier conversations. Plus, the interactive maps can be used by the corporate planning team to determine the best place for a new store, based on community demographics, competitor information, and sales trend information. They can even be viewed on an iPad.

“Ten years, our teams had to print out a map and take it with them. Now they can bring their mobile device, and have access to updated sales, demographics and other targeted information,” said Jillian Elder, director of enterprise location intelligence for Walgreens WBA .

Occasionally the maps serve a higher purpose. Managers in Texas in September were able to help local authorities predict the next targets for a local crime spree. “With some of our visualizations, we were able to put a stop to this,” Elder said.

Walgreens turned its maps interactive using the ArcGIS service from GIS company Esri, which has been its GIS partner since 2000.

The resource houses millions of maps available to companies that want to overlay proprietary data with the most up-to-data public information about specific locations. There are literally millions of maps published there. Most internal teams have access to basic information; Elder’s team created a special addition specifically for Walgreens’ real estate, strategy, and mergers and acquisition teams.

As of the latest FAQ information on its corporate web site, Walgreens generated more than $76 billion in sales last year across more than 8,300 locations across the United States and Puerto Rico.

For more details on the Walgreens mapping system, check out this video:

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