Her routine became collecting food, clothes, and money during the week and on weekends, traveling to Delano. When César Chávez went to the Bay Area in November of 1965 for a speaking tour, Kathy Lynch was the person organizing the rally at Sprout Hall at Berkeley, during which over $6,000 in donations for the strike were collected. From this point on, her involvement with the farmworker movement kept growing. She joined picket lines at the docks to stop grapes from being shipped abroad. In January of 1966, she moved to Delano to work for Jim Drake in the Albany Street office, keeping up with the correspondence from supporters. She was quickly put in charge to draft a report of the Friday night strike meetings, as she was able to understand Spanish, and was responsible for distributing the $5 weekly stipends to the NFWA volunteers.

During the march to Sacramento, she coordinated with Marshall Ganz how to bring supplies to marchers, and when she came back to Delano from Sacramento her friendship with Helen Chávez strengthened and she moved into the Chávez family house. Lynch played a major role in coordinating the successful San Francisco Bay Area boycott. In 1969, she returned to Delano to spend more time with her five children. Between 1969 and 1983, the year she left the union, Lynch took on different roles and projects, from directing the boycott information center to forming a co-op daycare center and serving as a director of the health clinic. Together with her husband, Lupe Murguía, and their five children, their family was one of the first to move to Stoneybrook Retreat, a previously tuberculosis sanatorium east of Bakersfield purchased by National Farm Worker Service Center that later became known as La Paz, when it became the headquarters for the union in 1973.