Geosynthetic-reinforced soil (GRS) systems have become competent alternatives to many critical structural traditional systems. Many of these systems involve the use of single reinforcement layer (e.g. reinforced pavement systems) or multiple reinforcement layers placed alternatively with compacted soil layers (e.g. reinforced retaining systems). While extensive research has been conducted to understand the behavior of these GRS systems, the identification of the shear band evolving at the soil-reinforcement interface has not been well-addressed yet. Shear band is deemed a key property that controls the behavior of the soil-reinforcement composite and its influence zone. Understanding the shear band evolution is par-ticularly relevant to optimize the use of reinforcement layers and their arrangement in GRS systems. This study involved a number of soil-reinforcement interaction testing setups to assess the evolution of soil-reinforcement interface shear band. These setups include the following: (1) a small-scale pullout equip-ment with a transparent side. This setup was used to evaluate the boundary effect on the soil-reinforcement behavior at small strain levels representative to many GRS applications; (2) a large-scale direct shear equipment with a transparent side to compare the shear band evolution in a pure interface shear condition. The paper presents the results of an implemented testing program that aimed at identify-ing the soil-reinforcement shear band.