"Smart-pooling" is a strategy to achieve high efficiency, sensitivity, and specificity in large-scale yeast two-hybrid screening. In smart-pooling, reagents are multiplexed in a highly redundant manner and the positives can be read out on the final selection plates without the requirement of any extra experimental steps. We have shown that the Shifted Transversal Design (STD), a powerful theoretical construction for smart-pooling, can be used in yeast two-hybrid interactome mapping. STD pooling can achieve similar levels of sensitivity and specificity as one-on-one array-based yeast two-hybrid, while the costs and workloads are much lower. This chapter focuses on the construction and usage of STD arrays for large-scale yeast two-hybrid interactome mapping.