Currently global food waste is over 931 million tons which is equivalent to about 20% of total food production. Therefore, there is a need to establish methodologies for the management of these food by-products to add value and thus contribute to the circular economy. The transformation of these wastes involves converting them into valuable resources such as fuels, energy, animal feed or high-value products. There is also the possibility of extracting bioactive molecules from these by-products, which could have applications in the food, pharmaceutical or cosmetic industries, this extraction has been performed by technologies such as microwave assisted extraction (MAE), high hydrostatic pressure extraction (HHP), pulsed electric field extraction (PEFE), supercritical fluid extraction (SFE), ultrasound assisted extraction (UAE) and enzyme assisted extraction (EAE), among others. The aim of this chapter is to analyze different technologies and strategies for the recovery of bioactive molecules from by-products, as well to mention the possible uses of these in various fields such as medicine, cosmetics, food, agriculture and to demonstrate their numerous advantages and limitations. The manuscript also provides a comprehensive analysis of the challenges encountered in the recovery of bioactive compounds and offers an insight into possible future developments.