The urgent need for sustainable agricultural practices, coupled with the well-documented limitations of chemical pesticides, underscores the importance of developing alternative strategies for plant disease management. This chapter examines microbial biocontrol as an ecologically sound approach that utilizes beneficial soil microorganisms such as Bacillus and Trichoderma species. These microbes employ multiple mechanisms, including direct antagonism through antimicrobial compound production, competition for nutrients and ecological niches, and the induction of systemic resistance in plants (ISR). Numerous case studies demonstrate their effectiveness under field conditions, although performance is strongly influenced by environmental factors, host–pathogen interactions, and the composition of the native soil microbiome. To improve reliability and scalability, this chapter highlights key strategies such as rigorous strain selection, optimized formulation and delivery systems, and the application of omics technologies to unravel microbe–plant–pathogen interactions. Overall, beneficial microbes represent a powerful tool for reducing chemical inputs, enhancing soil health, and promoting sustainable crop production. Continued research, particularly on microbial consortia, will be essential to fully integrate biocontrol into resilient and environmentally responsible agricultural systems.