Stimuli-responsive biodegradable polymers are employed to incorporate various therapeutic agents such as chemotherapeutic compounds, photosensitizers, molecularly targeted drug, and photothermal agents for constructing smart nanoparticles that can release drugs responding to different stimuli such as pH, enzyme, temperature, light, and temperature. In particular, some synergistic mechanisms are explored to maximize the anticancer efficacy between different therapeutic modalities (e.g. thermo-chemotherapy).