This final rule revises the current pesticide tolerance crop grouping regulations, which allow the establishment of tolerances for multiple related crops based on data from a representative set of crops. This rule creates five new crop groups, three new and two revised commodity definitions and revises the regulations on the interaction of crop group tolerances with processed food, meat, milk, and egg tolerances. These revisions will promote greater use of crop groupings for tolerance-setting purposes, both domestically and in countries that export food to the United States. This is the fourth in a series of planned crop group updates.