The preparation and evaluation of a new class of photoresponsive polymers are described on the basis of a process called quantum amplified isomerization (QAI). The QAI process utilizes photoinitiated, cation radical isomerization chemistry in a polymeric medium. Two classes of materials are described: one where the QAI reactant is molecularly doped in the polymer matrix and another where the reactant is part of a functionalized polymer. Quantum yield experiments demonstrate that the isomerization reaction can proceed by a chain process with modest efficiencies. Photochemical conversion experiments show that high extents of conversion of the QAI reactants are possible. The rate and extent of conversion are strongly correlated to the glass transition temperature of the polymer. For molecularly doped polymers, hypotheses to explain the high conversions based on diffusion or phase separation of the reactants were tested and excluded. Models are discussed to rationalize experimental factors that affect the quantum yields and the photochemical conversions.