Engineered skin substitutes were the first true clinical success of the principles of tissue engineering (Table 69–1). These clinically available products use autologous fibroblasts grown on a resorbable polymer scaffold for a single-layer product or fibroblasts covered with keratinocytes for a two-layer product. Recent products for promoting the healing of skin and dermal wounds also incorporate autologous fibroblasts delivered into the wound. Autologous chondrocytes are being used to heal damaged joints, and they have shown excellent results. Acellular collagen-based materials derived from human or animal dermis are being implanted for soft tissue reconstruction or hernia repair and become cellularized in vivo with autologous cells. Many engineered tissues are in clinical trials (Table 69–2) or under development, including those for bone, cartilage, nerve, skeletal muscle, small-diameter blood vessels, heart valves, and vital organs, including heart, liver, lung, and kidney.