The partnership between the American Hotel & Lodging Association and the Hotel Association of Canada to operate the Green Key Global hospitality sustainability certification program formally will take effect April 1, the associations announced this week. The groups in September announced they would bring the Green Key program, which HAC has used since 1994 to rate participating properties' sustainability practices, to the United States. An AHLA spokesperson clarified to BTN this week that the associations would "jointly own and operate Green Key" in the U.S. and Canada "via a partnership structure."