The water content of clouds, whether in liquid or ice form, is a key variable to be measured when either calibrating remote sensing systems or when calculating the climatological effects of clouds. While a variety of sensors exist for making these measurements, all of the existing sensors require far too much power or other energy input to be used on small platforms with limited payloads such as UAVs, balloons, and kites. Anasphere has developed and completed preliminary testing of a novel cloud water content sensor which does not require any external energy input, but is capable of measuring both liquid water and ice content of clouds. Preliminary results have been extremely promising. Phase I work will include the fabrication and demonstration of proof-of-concept sensors based on the designs investigated in the preliminary research, culminating in a balloon-borne flight with a radiosonde through a cloud. Phase II work will include the refinement of the design, extensive laboratory testing, and extensive field intercomparisons and trials.