“…The stimuli-sensitive nanocarriers maintain their stealth function throughout circulation, and upon arrival at the specific tumor site, undergo rapid changes, such as aggregation, disruption, and permeability changes, which trigger drug release when exposed to a particular tumor microenvironment [2,52,53]. In order to achieve site-specific triggered drug release, several strategies have been investigated, for example, internal stimuli that are characteristic for a tumor microenvironment (low pH, redox potential, high temperature, and enzymes) and external stimuli, such as magnetic fields, ultrasound, or light [54][55][56]. Both internal and external stimuli-sensitive liposomes will be addressed further, classified according to the mechanism exploited.…”