A versatile polymeric waveguide technology is proposed for low-cost high-performance photonic devices that address the needs of both the telecom and the datacom industries. We have developed advanced organic polymeric materials that can be readily made into both multimode and single-mode optical waveguide structures of controlled numerical aperture (NA) and geometry. These materials are formed from highly-crosslinked acrylate monomers with specific linkages that determine properties such as flexibility, toughness, loss, and stability with temperature and humidity. These monomers are intermiscible, providing for precise adjustment of the refractive index from 1.3 to 1.6. Waveguides are formed photolithographically, with the liquid monomer mixture polymerizing upon illumination in the UV via either mask exposure or laser direct-writing. A wide range of rigid and flexible substrates can be used, including glass, quartz, oxidized silicon, glassfilled epoxy printed circuit board substrate, and flexible polyimide film. We discuss the use of these materials on chips, on multi-chip modules (MCM’s), on boards, and on backplanes. Light coupling from and to chips is achieved by cutting 45° mirrors using Excimer laser ablation. Fabrication of the planar polymeric structures directly on the modules provides for stability, ruggedness, and hermeticity in packaging.