The reality is that many businesses, large and small, have long used undocumented workers to pad their bottom lines. Just consider the agricultural workforce. In California alone-where the $45 billion-a-year agricultural sector supplies more than half the produce consumed in the United States-between 40 and 50 percent of the workforce is made up of undocumented workers. No wonder California has been the site of some of the most important immigrant labor struggles, brought to the consciousness of many Americans in the 1960s and 1970s by the great United Farm Workers leader, Cesar Chavez. That struggle continues today.