This chapter aims to discuss several aspects of marker-assisted selection (MAS) with a focus on disease resistance. The historical significance of disease resistance breeding, the economic impact of crop diseases, and the growing importance of creating disease-resistant cultivars in the face of climate change are deliberated in this chapter. The factors that affect the successful application of marker-assisted selection (MAS) for the development of disease-resistant varieties are thoroughly discussed. These factors include the type of markers used, linkage distance, phenotyping, size of mapping population, screening techniques, mode of inheritance and available genetic and genomic resources. Additionally, effective instances of gene pyramiding, foreground and background selection, and disease-resistant cultivars developed globally using MAS are embodied. We also have emphasized the role of contemporary phenotyping methods, speed breeding, and genotyping platforms in improving the efficacy of MAS in near future.