A Practice Note discussing ambush marketing in the US. This Note covers direct, indirect, and incidental ambush marketing, including the sub-categories of predatory, coattail, self, associative, distractive, unintentional, and saturation ambushing, protection under the Lanham Act and case law, and how ambush marketing can violate state unfair competition and contract laws. This Note also discusses statutory protection and enforcement of the United States Olympic Committee (USOC), including the Amateur Sports Act of 1978, the Ted Stevens Olympic and Amateur Sports Act, and Rule 40.3 of the Olympic Charter.