Objective Un Abrazo Para La Familia (A Hug for the Family) is an intervention designed to increase the accessibility of cancer information to low‐income and medically underserved co‐survivors of cancer. Co‐survivors are family members or friends of an individual diagnosed with cancer. Our goal was to increase socio‐emotional support for these co‐survivors and improve skills in coping with cancer. The purpose of our pilot study was to explore the effectiveness of the intervention in increasing cancer knowledge and self‐efficacy among co‐survivors. Methods Un Abrazo consisted of three one‐hour sessions, in either Spanish or English. Sessions were delivered by a trained promotora (community health worker), in partnership with a counselor. Sixty participants completed measures of cancer knowledge and self‐efficacy preceding (pre‐test) and following the intervention (post‐test). Results From pre‐test to post‐test, the percentage of questions answered correctly about cancer knowledge increased (p < 0.001), as did ratings of self‐efficacy (p < 0.001). Decreases were seen in ‘Do not know’ responses for cancer knowledge (p < 0.01), with a negative correlation between number of ‘Do not knows’ on cancer knowledge at pre‐test and ratings of self‐efficacy at pre‐test (r = −0.47, p < 0.01). Conclusions When provided an accessible format, co‐survivors of cancer from underserved populations increase their cancer knowledge and self‐efficacy. This is notable because research indicates that family members and friends with increased cancer knowledge assume more active involvement in the cancer care of their loved ones. Copyright © 2011 John Wiley & Sons, Ltd.