Having covered the discovery of microRNAs, the expansion of their universe, the cataloguing of their presence in the kingdoms of life, how they control gene activity and why this is so important, and finally how they are applied in science and medicine, we come to the end. Here, there is an opportunity to ask, ‘What’s next?’ What are some of the most exciting directions in current microRNA research and what lies over the horizon? This final chapter explores some of the latest questions. What is the totality of the influence of microRNAs in the most complex systems in the body and what technologies will we use or need to answer these questions? Are there components of the microRNA pathway still to be found? Some of the most advanced applications of microRNAs are in the field of synthetic biology, where microRNAs can be useful in engineered cells and systems. After such a richness of discovery about microRNAs during development, research is now asking questions about what microRNAs do towards the ends of our lives. Finally, a speculation about whether microRNAs or molecules like them exist beyond the borders of Earth, wherever else life is found in the universe.