Microphysiological systems (MPS), i.e., miniaturized mimics of active biological systems, are considered resourceful tools for facilitating drug development. It presupposes that a microphysiological system can respond as organs and tissues in the human body to new drug candidates and that relevant cellular response can be monitored. If, or when, this is possible, microphysiological systems have the potential to support and accelerate the development and testing of new drug candidates. So far, the focus has been more on the design and fabrication of the microarchitecture of the MPS to recreate their cellular counterparts as closely and realistically as possible. Commercial MPS devices have been developed that focus on advanced technological design solutions, sometimes more than their actual biological functionality. This chapter discusses in brief terms the prerequisites for the design and construction of MPS devices in relation to their utility for drug development and testing in a more holistic manner. The use of induced pluripotent cells as a prime source for mimicking the in vivo conditions of diseased conditions is mainly considered. Existing limitations and needs are highlighted in relation to the space for improvements, based on recently published results.