Tissue engineering and regenerative medicine aim to develop biological substitutes that restore, maintain, or improve damaged tissue and organ functionality. While tissue engineering and regenerative medicine have hinted at much promise in the last several decades, significant research is still required to provide exciting alternative materials to finally solve the numerous problems associated with traditional implants. Nanotechnology, or the use of nanomaterials (defined as those materials with constituent dimensions less than 100 nm), may have the answers since only these materials can mimic surface properties (including topography, energy, etc.) of natural tissues. For these reasons, over the last decade, nanomaterials have been highlighted as promising candidates for improving traditional tissue engineering materials. Importantly, these efforts have highlighted that nanomaterials exhibit superior cytocompatible, mechanical, electrical, optical, catalytic and magnetic properties compared to conventional (or micron structured) materials. These unique properties of nanomaterials have helped to improve various tissue growth over what is achievable today. In this review paper, the promise of nanomaterials for bone, cartilage, vascular, neural and bladder tissue engineering applications will be reviewed. Moreover, as an important future area of research, the potential risk and toxicity of nanomaterial synthesis and use related to human health are emphasized. (C) 2008 Elsevier Ltd. All rights reserved.