Integrating spheres are ideal tools for measuring optical radiation. Designed to spatially integrate radiant flux, these integrating spheres can be coupled with a sensor to create a radiometer, photometer, or spectroradiometer. Such a setup would permit the measurement of total geometric flux emanating from a light source or the flux density of an illuminated area. The spheres also provide an ideal method to measure output of high power lasers and laser diodes. Our spheres can also be setup to measure reflectance and transmittance of materials.