Publisher Summary This chapter provides an overview of the breeding progress for some of the most important agronomic traits and summarizes molecular technologies associated with plant breeding, highlighting future perspectives that could result from the integration of recent advances in physiology, genomics, and biotechnology. Plant breeding can be described as the continuous accumulation of superior alleles (i.e., genes encoding useful traits) in the gene pool of the cultivated elite lines. The cultivated germplasm represents only a minimal part of the whole germplasm of a given crop species. Under these conditions, breeding has two main targets: to search for new useful alleles worthy to be introduced into the elite lines (also called “prebreeding”) and to promote the recombination within the elite germplasm to find the best combinations among the best alleles. Prebreeding refers to the transfer or introgression of genes and gene combinations from unadapted sources into breeding materials. There are two distinct approaches for using wild species, exotic, and landrace germplasm in plant breeding: introgression and incorporation. Introgression indicates the transfer of one or a few alleles from exotic genotypes to adapted bred cultivars that lack the allele(s) controlling a specific trait. Incorporation refers to a large-scale effort aiming at developing locally adapted genotypes using exotic germplasm, which is likely to broaden the genetic base of new breeding materials.