Breeding strategies that combine genomic and phenotypic selection can maximize annual selection gain for improving multiple traits in crops. Using a selection index can significantly impact the selection gain for individual traits. One-stage genomic selection followed by one-stage phenotypic selection outperforms classical two-stage phenotypic selection. The choice of selection index, such as Smith-Hazel or base index, can lead to higher selection gains for net merit and individual traits compared to other indices. The correlation between traits, variance components, and economic weights play a crucial role in determining the effectiveness of the breeding strategy.