Leaf and yellow rusts are major diseases of wheat worldwide. Deployment of major, race-specific resistance genes, either singly or in combinations, has not given resistance stability because of pathogens' ability to evolve rapidly. Breeding for minor genes based leaf rust resistance in wheat initiated at CIMMYT during early 1970s due to frustrations caused by the “breakdowns” of race-specific resistance in about 3 years in the northwestern Mexico. Plants that displayed intermediate rust severities, or displayed slow rusting resistance, and produced good plump grains were retained in early years. This led to the development of several wheat cultivars whose moderate leaf resistance continues to remain effective. Genetic studies in late 1980s indicated that such cultivars often carried 2 or 3 slow rusting minor genes that had small to intermediate but additive effects. Intercrossing such cultivars and selection in the field under controlled rust epidemics produced wheat genotypes that not only had good yield potential but also combined between 4-5 minor genes that conferred near-immune levels (almost disease free) of resistance to both leaf and yellow rusts. Further genetic and molecular mapping studies have shown that slow rusting resistance to leaf and yellow rusts in CIMMYT-derived wheats often involves linked/pleiotropic minor genes, such as Lr34/Yr18 and Lr46/Yr29 in chromosome 7DS and 1BL, respectively. During mid 1990s we initiated a targeted transfer of such resistance using the ‘Single-Backcross, Selected-Bulk' breeding approach. This approach not only favors the selection of resistance but also allows simultaneous progress in grain yield and quality characteristics. Several diverse wheat genotypes have been developed and distributed worldwide for testing and probable releases to achieve a long-term stability of resistance. Molecular marker aided selection for slow rusting resistance genes remains a challenge due to the lack of tightly linked markers, although chromosomal locations are now known for several such genes.