Abstract: The present invention provides a water soluble, nonpeptidic polymer comprising two or more alkylene oxide-based oligomers linked together by hydrolytically degradable linkages such as carbonates. Typically, the oligomer portion of the polymer is an amphiphilic triblock copolymer having a central propylene oxide block or butylene oxide block positioned between two ethylene oxide blocks. The polymer can be hydrolytically degraded into oligomers under physiological conditions. In aqueous media, the polymer preferably forms thermally reversible, hydrolytically degradable hydrogels that can be used, for example, for drug delivery and related biomedical applications.