Ahold USA became the largest conventional grocer in the United States to join the Coalition of Immokalee Workers' (CIW) Fair Food Program.
CIW's Fair Food Program protects farmworkers' rights, including fair wages, safety compliance and protection against sexual harassment.
By agreeing to join the Fair Food Program, Ahold's 780 supermarkets across 14 states will only do business with suppliers that meet CIW's criteria.
Wal-Mart agreed last year to pay one more cent per pound for tomatoes in conjunction with the Fair Food Program.
Ahold USA owns Stop & Shop, Giant Foods of Landover, Giant Foods of Carlisle, Martin's and online grocery delivery service Peapod.