Groupon clones providing collective buying deals via websites emerged in Vietnam, taking inspiration from Groupon.com. The largest clones were NhomMua.com, Hotdeal.vn, MuaChung.vn and CungMua.com. They offered daily deals with discounts to customers who reached a minimum purchase threshold, but faced limitations from the underdeveloped e-payment market requiring high costs for cash-on-delivery orders. The long-term sustainability of the Groupon clone business model in Vietnam was uncertain given high operating costs.