Loss and failure of organs and tissues are obviously major health-care problems. Living-organ and tissue transplantation have been the easiest solutions to these problems so far, but having enough donor material for all patients is unrealistic. Tissue engineering is an emerging area in biomedicine that may help solve this problem. Methods involved in tissue reconstruction include using cells alone or the association of cells with tridimensional scaffolds for more complex tissues, while organ reconstruction requires cells, scaffolds, homing systems and integration with mechanical systems and microelectronic devices. Here, the authors review the state of the art in tissue engineering and also touch upon organ engineering.