Analysis is presented of resonators consisting of a section of a dielectric-loaded waveguide shorted at both ends. The analysis includes resonant frequency calculations, mode charts, and unloaded Q computations. Numerical results are presented for the unloaded Q's of various modes, as a function of the resonator parameters. Effects of losses in different parts of the resonator wall on the unloaded Q are discussed, and methods of improving these Q's are explored. Experimental verification of the theoretically derived results is made for a number of resonators, and the measurements agree closely with theory.