Smart drug delivery vehicles, which are responsive to endogenous or exogenous stimuli, are appealing therapeutic platforms with less side effects and enhanced treatment efficacy for the aim to echo the increased requirements of precision medications (Fig. 6.1). On the basis of the stimuli-responsive property, drugs could be controllably released and accumulated in the region of interest by designing appropriate delivery vehicles that are sensitive to endogenous physiological signals or extrinsic stimulations. Here, various endogenous and exogenous stimulations-responsive drug vehicles are presented and discussed.