MGS Research has pioneered the development of polymer gel dosimeters, using both MRI and optical CT scanning. Our goal in Phase I will be to prove the feasibility of an innovative two-phase nanostructured polymer gel for quantitative 3D radiation dosimetry. The new gel structure can be described as a "single-hit 3D photon counter" that can be expected to be linear with dose and to be dose-rate independent. Moreover, it will be characterized by greater reproducibility, accuracy and stability of the dose response. As a result, the nanostructured polymer gels will be more suitable than the existing single-phase gels for the quantitative 3D radiation dosimetry and high-precision quality assurance, which are very much needed in intensity modulated and 3D conformal radiation therapy.