During my Ph.D. studies, I focused on developing theoretical models capable of predicting the mechanical strength of body-centered cubic (BCC) alloys, spanning from dilute alloys to high-entropy alloys. This research tackled a multi-scale problem, as the material's strength, a macro-scale property, was directly linked to the underlying dislocation motion mechanisms occurring at the atomic level. To accurately capture the behavior, I relied on input material properties obtained from Quantum level simulations, such as Density Functional Theory (DFT). By bridging these scales and incorporating insights from atomic-level simulations, I aimed to provide a comprehensive understanding of the mechanical behavior of BCC alloys, enabling more precise predictions of their mechanical strength across a range of alloy compositions