Callisto (mesotrione) and Impact (topramezone) are the two HPPD-inhibiting herbicides that are currently labeled for postemergence use on sweet corn. Laudis (tembotrione) is another HPPD-inhibiting herbicide that is currently under development by Bayer CropScience for postemergence use on sweet corn. Laudis may be available as soon as 2008 for commercial use. While Callisto is primarily for broadleaf weed control, Impact and Laudis are active on both broadleaf and grass weeds. Impact and Laudis would be the only other options for postemergence grass control other than Accent (nicosulfuron) and Poast (sethoxydim) on sethoxydim-resistant (SR) sweet corn hybrids. Accent has a risk of injuring sensitive fresh market and processing hybrids and only a limited number of SR sweet corn varieties are currently available. Previous research has shown hybrids can have differential tolerance to Callisto, however, little information has been provided about potential injury risks with Impact or Laudis.