To achieve these aims, the research team will conduct a randomized controlled trial (RCT) among 300 breast cancer survivors (with an expected completed sample size of 250) with Stage I-III BC who have received adjuvant CT or CT and radiation. Within this RCT, MBSR(BC) will be delivered to a sub-population of Spanish speaking breast cancer survivors. Participants will be randomly assigned in a 1:1:1 ratio to 1 of 3 conditions (1) the 6-week MBSR(BC) program; (2) the 6-week BCES program; or (3) UC. However, once the UC condition has reached a total of 30 participants, then randomization at the baseline assessment will occur in a 1:1 ratio to 1 of 2 conditions: (1) MBSR(BC) and (2) BCES.