As one of the most interesting class of smart materials, chromic materials which show a colour change when exposed to an external stimulus are generally employed in high-tech applications being exploit the chromic effect induced by the stimulus, for instance in thermometry, electronics, ophthalmics, photonics, biomedicine, etc. The colour change, whether it is from white to black, from colourless to coloured or from one colour to another could be induced by heating (thermochromism), solvent quality change (solvatochromism), mechanical stress (mecanochromism), ions detection (ionochromism), electromagnetic radiation (photochromism), biological agents detection (biochromism) etc. [1]. More than half a century after the launch on the market of high performance polymers, aromatic polyimides are still a subject of intense research efforts, both in academic and application studies, due to the excellent combination of high thermal resistance and superior mechanical properties, long-term use and an advantageous synthetic pathway that makes them suitable for advanced technologies [2]. Due to these superior properties, the application field of polyimide has generally been enlarged from printed circuit boards and electrical insulation layers in microelectronics to functional layers of humidity sensors, shielding layers for sensor surfaces and novel platforms for thermal sensor devices, temperature sensor arrays, micro-hotplates integrated into gas sensors and biosensors [3]. Although these polymers exhibit interesting properties, addressing the polyimide materials design issue as to present interesting colour changes in response to an external stimulus and, based on them, sensing ability, is extremely challenging. Based on these considerations, we report some of our attempts to develop polyimide materials with chromic response to external stimuli, such as pH, electrical potential, light radiation or metal ions. By using some tools provided by organic chemistry, the receptors were tailored with specific functionalities which allowed their easy incorporation into polyimide chains, as well as to endow these polymers with both inherent properties and recognition capability towards various surrounding stimuli.