Go into a shopping center or downtown restaurant, even a casino or concert hall, and you may be in a community improvement district. And unless you check your receipt, you may never know it. CIDs allow additional sales taxes, property tax assessments or both to pay for improvements or services that have some public good. Use of the tool has mushroomed in the Kansas City area. Kansas City alone has 27 CIDs that, collectively, are expected to raise about $10 million in the fiscal year ending April 30.