A promising means to address the limited supply of donor tissue is through the generation of artificial organs consisting of cells and materials. Progress towards this goal is limited by three main obstacles namely the generation of a sufficient number of cells specific to the organ, the arrangement of these cells in a functional tissue architecture and the delivery of nutrients and removal of waste from the tissue mass. This chapter describes the emerging approaches that may be achieved by the control of stem cell differentiation, control of the local tissue environment on the microscale, and the generation of complex structures containing multiple cell types.