Many small noncoding RNAs (sRNAs) in bacteria act as posttranscriptional regulators by base pairing to their message targets. TargetRNA is a program that predicts the targets of a sRNA by identifying messages with significant potential to base pair with the sRNA. Since base pairing potential alone is insufficient to accurately identify sRNA targets, TargetRNA integrates several additional features of RNA interactions when predicting regulatory targets of a sRNA. In this chapter, we provide a detailed guide on how to use TargetRNA to identify targets of sRNA regulation.