Over the last decades, the number of dyes with appealing photophysical properties has drastically increased, allowing development of novel fluorescence-based technologies such as OLEDs , sensors or bio-labeling . Application of fluorescent materials requires a thorough understanding of the behavior of molecules in variable environments with emphasis on controlling photophysical properties in the intramolecular and intermolecular regimes. In that regard, the sensitivity of the dye introduced by the intramolecular charge-transfer (ICT) can be monitored by changes in absorption, emission, Stokes shift, and fluorescence quantum yield (FQY). The inter molecular forces, such as hydrogen and halogen bonds or stacking can lead to aggregation, which affects the same set of photophysical properties, providing the aggregation-induced emission (AIE) or aggregation-caused quenching (ACQ) mechanisms for FQY control. The number of structural features of a molecule (rigidity/flexibility, proton transfer, hydrophobic/hydrophilic nature of dye) deliver the technical tools to influence subtle intermolecular interactions and thus achieve desired aggregation-induced emission change.