Fifty years of sales tax policy in the United States is coming to an end. In South Dakota v. Wayfair Inc. (Wayfair), the U.S. Supreme Court on June 21 ruled in a 5-4 decision that the physical presence standard for sales tax collection is no longer the law of the land. Retailers across the nation must prepare for a profound increase in sales tax collection responsibilities as states adapt their laws to this new judicial standard.