As tissue engineering advances from developing simple two-dimensional (2D) constructs towards the development of thick three-dimensional (3D) tissues on the scale of human organs, the transport of oxygen and nutrients to cells via functional vasculature becomes a paramount engineering challenge. Our field lacks methodologies to fabricate the requisite architecture, while quantitative workflows to predict and evaluate the effectiveness of a given design are also lacking. We and others are adapting 3D printing technologies to generate complex and bioinspired vascular geometries that can support the transport needs of large 3D tissues. We applied computational tools and linked them to experimental analyses of convective and diffusive transport provided by three-dimensional vascular networks. Human vasculature is multiscale with fractal complexity; to begin to approach this complexity we designed and studied mimics of specific aspects of vascular anatomy such as branching blood vessel networks and intravascular bicuspid valves. Our perfusable vessels supported arterial pressures, so we further investigated the feasibility of surgically connecting our constructs directly to host vasculature in small and large animal studies. The objective of this work is to close the loop between computational and experimental models involving blood flow and mass transport in vascular networks, allowing scientists to more effectively design and fabricate vascularized tissues. This work provides a quantitative roadmap for the design of vascular networks and the evaluation of their function within 3D tissue constructs.