"Riding herd" is a common phrase used to describe the act of supervising or monitoring a group of people or activities. However, there are several synonyms that can be used to express the same meaning. These include "keeping watch," "keeping an eye on," "overseeing," "managing," "directing," "controlling," "guiding," "leading," "superintending," "monitoring," and "regulating." Each of these words conveys a sense of responsibility and authority, making them appropriate alternatives to "riding herd." Depending on the context, one of these synonyms may be more appropriate than the others. Ultimately, the choice of word will depend on the writer's intended tone and message.