3D bioprinting is expensive, so cost can be an obstacle. After mastering that, there are still some science “miracles” that need to happen before complex bioprinted tissues can be implanted. Printing a large tissue cell by cell will never produce a functioning organ – it takes too long, and in some cases, many specialized cell types are needed that are difficult to derive or isolate. Thus, we started working with stem cell derived organoid tissue to capture the multitude of cell types and used 3DP to provide the architecture and large vascular conduits requisite for a growing tissue. Challenges that the field must still tackle include ensuring complete differentiation of stem cell derived organoids, enabling printed and stem cell derived vascular networks to integrate, and finally creating printed tissue that is not rejected by the patient.