The high uptake of droplet microfluidics in multidisciplinary research is mainly due to its capability of being a micro-scale laboratory with high versatility in controlling each microreactor. Through the implementation of three main manipulation methods, multiple reactions can be produced and subsequently used for different applications. Droplets of a predetermined medium are first generated. Subsequently, the coalescence of different droplets can also take place to mix different reagents. Finally, sorting of droplets according to pre-set variables is carried out, facilitating the analysis of results. Each manipulation method, however, can be carried out using a variety of active control methods. These can be categorized into electrical, magnetic, thermal, pneumatic, and occasionally acoustic and optical means. Further elaboration is provided in this chapter to illustrate these methods with the repertoire of mechanisms developed for these purposes. The advancement of such techniques enables high selectivity with minimal waste of resources, reducing the carbon footprint of laboratories while concurrently pursuing science.