Abstract: The options for increasing food production by at least 70% over the next four decades so as to keep pace with a rapidly increasing human population are bedeviled by erratic climatic conditions, depleted arable lands, dwindling water resources and by the significant environmental and health costs for increasing the use of agrochemicals. Enhanced productivities through “smart” crop varieties that yield more with fewer inputs is a viable option. However, the genetic similarities amongst crop varieties—which render entire cropping systems vulnerable to the same stresses—coupled with unvarying parental materials limit the possibilities for uncovering novel alleles of genes and, hence, assembling new gene combinations to break yield plateaux and enhance resilience. Induced mutation unmasks novel alleles that are harnessed to breed superior crop varieties. The historical antecedents, theoretical and practical considerations, and the successes of induced mutations in crop improvement are reviewed along with how induced mutagenesis underpins plant functional genomics. The roles of cell and molecular biology techniques in enhancing the efficiencies for the induction, detection and deployment of mutation events are also reviewed. Also, the integration of phenomics into induced mutagenesis and the use of pre-breeding for facilitating the incorporation of mutants into crop improvement are advocated.