As Multi-Material Additive Manufacturing (MMAM) technologies continue to develop and mature, so too will the diversity and functionality of compatible material systems. Of particular interest is the ability to deposit strong, anisotropic fibers via an AM process in order to create strong, stiff, and functional 3D printed composites. Using a combination of multi-physics simulation software (COMSOL) and a flexible optimization strategy, the best fiber/matrix orientation and distribution can be determined for one or multiple objectives. Emphasis is placed on minimizing stress and strain, delamination potential, maximizing stiffness, etc. Using a desktop 3D printer capable of printing a Nylon matrix and multiple types of continuous fiber (carbon, glass, Kevlar), both optimized and non-optimized designs are fabricated for comparison and validation of the optimization. Validation and characterization tools, including X-Ray Tomography and Digital Image Correlation (DIC), are used to evaluate performance in multiple spatial dimensions with high precision.