- Abstract. Tissue engineering entails the in vitro or in vivo generation of replace-ment tissues from cells with the aid of supporting scaffolds and stimulatingbiomolecules, in order to provide biological substitutes for restoration and mainte-nance of human tissue functions. In this review, we summarize the main classesof degradable polymeric scaffolds, natural and synthetic ones, and the evolutionmade in this field from adaptation of materials in clinical use to the fabrication of“designer” scaffolds. TISSUE ENGINEERING—BASIC PRINCIPLES Tissue engineering is an interdisciplinary field thatapplies the principles of engineering, materials, and lifesciences to the development of biological substitutes forrestoration and maintenance of human tissue functions. 1 This new and emerging technology entails the in vitro orin vivo generation of biological tissue from individualcells with the aid of supporting scaffolds and stimulat-ing biomolecules. The supporting scaffold temporarilyreplaces the function of the natural extracellular matrix(ECM), thus enabling the seeded individual cells toregenerate cell–cell and cell–matrix interactions, lead-ing to the formation of a functioning tissue. As potentialreplacements of ECM, implanted scaffolds can alsofunction as in vivo guided-regenerative matrices by in-ducing remaining healthy patient’s cells to populatethem.A large portion of the research in this field has beendevoted to designing the ideal scaffold that would bestmimic the native extracellular matrix. In this review, wedescribe the main classes of degradable polymeric scaf-folds that have been developed since the “birth” oftissue engineering until today. Our goal is to describethe evolution of this field, from adaptation of materialsin clinical use to the fabrication of “designer” scaffolds.