"An Opportunity Zone is an economically-distressed community where new investments, under certain conditions, may be eligible for preferential tax treatment. Localities qualify as Opportunity Zones if they have been nominated for that designation by the state and that nomination has been certified by the Secretary of the U.S. Treasury via his delegation of authority to the Internal Revenue Service."
Per the IRS. See more at https://www.irs.gov/newsroom/opportunity-zones-frequently-asked-questions