Multi-physical transport processes on multiple scales occur in electrochemical devices and components for CO2 electroreduction. These complex coupled transport processes determine the local environment in the catalyst layer and subsequently also the reaction rates at the catalytic sites. I will discuss how the coupling between atomistic- and molecular-scale models, microkinetic models, and continuum-models can help in improving the understanding of the elecotrchemical CO2 reduction. I will focus on silver as catalysts and discuss how (i) the presence of reaction products can affect the performance, (ii) how the electrolyte nature can affect the selectivity and activity [1], (iii) how pulsed operation can help to improve performance, and (iv) how the mesostructure of the electrode can affect the local conditions [2,3]. All these modeling efforts will demonstrate how multi-scale and multi-physics models can be used to guide the design, operation and material choice for electrochemical CO2 reduction. In fact, such models are essential for the understanding of electrochemical CO2 reduction since experimental investigations cannot provide the detail and locally resolved information required.