Horizontal integration occurs when a firm enters a new business (either related or unrelated) at the same stage of production as its current operations. For example, Avon's move to market jewellery through its door-to-door sales force involved marketing new products through existing channels of distribution. An alternative form of that Avon has also undertaken is selling its products by mail order (e.g., clothing, plastic products) and through retail stores (e.g.,Tiffany's). In both cases, Avon is still at the retail stage of the production process.