RIDE HERD ON

{v. phr.} 1. To patrol on horseback around a herd of animals to see that none of them wanders away. * /Two cowboys rode herd on the cattle being driven to market./ 2. {informal} To watch closely and control; take care of. * /A special legislative assistant rides herd on the bills the president is anxious to have congress pass./ * /Mary rode herd on the small children walking home from school to keep them from running into the street./