Key Points The extracellular matrix (ECM) is the largest component of normal skin and gives the skin its unique properties of elasticity, tensile strength and compressibility. In acute wounds the provisional wound matrix, containing fibrin and fibronectin, provides a scaffolding to direct cells into the injury, as well as stimulating them to proliferate, differentiate and synthesise new ECM. Chronic wounds contain increased levels of inflammatory cells, giving rise to elevated levels of proteases that appear to degrade the ECM components, growth factors and receptors that are essential for healing. Understanding of the importance of re-establishing a functional ECM in chronic wounds has led to technical advances and the development of products that reduce excessive protease levels or contribute functional ECM proteins, thereby facilitating the healing process. Abstract The extracellular matrix (ECM) is the largest component of the dermal skin layer and the synthesis of ECM is a key feature of wound healing, especially when there has been a significant loss of tissue that precludes closure by primary intention. This article discusses the proteins contained in the ECM of normal skin that are important in the healing of acute and chronic wounds. In addition, the theory that the high levels of proteases found in chronic wounds impair healing by degrading essential components of the ECM is discussed using data from cell culture experiments and immunohistochemical analyses of wound biopsies. As a consequence of this theory new dressings have been developed that are designed to reduce protease levels in wound fluids by