Glaser was commissioned by United Farm Workers (UFW) to produce this poster in support of a May 10, 1969, international boycott of California table grapes in support of farm workers who were being exploited by growers and exposed to toxic chemicals. The movement began in Delano, California, in 1965. Below the sinister image of a bunch of grapes in the form of a skull against a dark ground is a quote from the famous “Letter from Delano”; in this long and impassioned missive, written a few weeks before the boycott, Cesar Chavez, the Chicano civil rights leader and labor activist who had founded UFW, addressed E.L. Barr, president of the California Grape and Tree Fruit League.