Breeding improved winter wheat cultivars means to select lines with combinations of a multitude of relevant traits, particularly grain yield and yield stability, end-use quality and resistance to the relevant biotic and abiotic stresses. More than 30 traits need to be considered simultaneously, making wheat one of the most complex crops to breed. Multi-trait selection is a cumbersome topic. Line breeding typically selects highly heritable traits in early generations often relying on visual scores and rigorous culling and the more difficult traits that require replicated and costly phenotyping in later stages of line selection. Selection for one trait may lead to wanted or unwanted correlated selection responses in other traits. Even for non-correlated traits selection for some traits in early generations of a breeding population may reduce the available variation for other traits in later selection rounds. These factors may be reasons why even in populations descending from crosses of resistant parents, not the best resistant progeny will be selected, particularly if the resistance trait will be evaluated later in the breeding scheme and only a small number of lines remain available for final evaluation and advancement as cultivar candidates.