Bioengineers study the development of organ-specific tissues in the lab for therapeutic applications. However, the process is highly challenging, since it requires the fabrication and maintenance of dense cellular constructs composed of approximately 108 cell/mL. Research teams have used organ building blocks (OBBs) composed of patient-specific-induced pluripotent stem cell (iPSC)-derived organoids as a pathway to achieve the requisite cell density, microarchitecture and tissue function. However, OBBs hitherto remain to be assembled into 3-D tissue constructs. In a recent report, Mark A. Skylar-Scott and an interdisciplinary research team at the Wyss Institute for Biologically Inspired Engineering and the John A. Paulson School of Engineering and Applied Sciences at Harvard University, developed a new biomanufacturing method.