Male-sterile hybrids of flue-cured and burley tobaccos are becoming increasingly common throughout many of the world's larger tobacco production areas. Grower and industry demands for disease resistant genotypes with acceptable leaf quality traits have helped fuel this trend, and several of the major breeding programs are using hybridization of pure lines to create hybrids that combine the desirable characteristics of both parents. Unlike hybrids of other major agronomic crops such as corn or sorghum, tobacco does not display a high degree of heterosis for yield and plant size. Indeed, additive effects account for nearly all of the genetic variation, and little or no dominance genetic effects have been measured. The value of hybrids in tobacco can be attributed to improvements less easily measured than large heterotic effects. These include incrementally greater yield, the combining of traits unique to each parent, and potentially wider adaptation. Results from performance trials will be compared with reports from published literature to provide an overall estimate of tobacco hybrids to the industry.