Aqueous soluble polymers designed to rapidly degrade by an intramolecular assisted acid catalysed mechanism were prepared. Degradation studies at pH 5.5 and 2.0 exhibited a rapid first phase followed by a slower phase and incomplete degradation to macromonomeric species. The fast phase was attributed to repeat units containing a carboxylic acid pendent chain cis to an amide bond in the polymer mainchain and the slow phase by the absence of this free carboxylic acid moiety.