While the field of tissue engineering holds great promise to address the critical shortage of tissues/organs for transplantation, a key challenge that remains is vascularizing large constructs. Presented herein is a strategy to develop a prevascular network within engineered tissues to facilitate early anastomosis with host vasculature and perfusion. A co-culture system was established that uses endothelial cells and supporting mesenchymal stem cells to generate aggregates of cells containing a network of prevascular cord and plexus-like structures reminiscent of embryonic vasculogenesis. Aggregates comprised of 50,000 cells were 537 µm in diameter, just beyond the limit of oxygen diffusion and thus appropriate for a vascularization study. Fibroblast growth factor 2 (FGF-2) was then shown to be a sufficient media supplement to enhance early vasculogenesis within the first week. A bioink of these prevascular aggregates in fibrinogen was then 3D printed into a thrombin-containing hydrogel slurry temporary support, resulting in fibrin encapsulated prevascular aggregates. These prevascular structures were shown to persist for 7 days of tissue culture. A minimum pre-printing culture time of 7 days was demonstrated to maintain prevascular structures post-printing. This system allows for the precise spatial control of prevascularized constructs that may ultimately enhance microvascularization upon transplantation in vivo.