In this chapter, we first summarize new predictions concerning the process zone—its properties and its impact on individual cracks and dislocations, as well as on the macroscopic properties of solids—arising from the field-theoretical approach. We then provide a list of problems that remain unsolved and can be addressed in future work. By tackling these and many other open questions not listed here, future research can further elucidate the complexities of defect–process zone interactions, their dynamics, and their broader implications for material behavior.