Purpose To determine 1-year outcomes of a four-component behavioral therapy (BT) sleep intervention (Individualized Sleep Promotion Plan [ISPP]) versus a healthy eating control (HEC) on cancer related fatigue in women receiving breast cancer adjutant chemotherapy treatment (CTX). Patients and Methods A total of 219 participants from 12 oncology clinics were randomly assigned in a clinical trial. Before CTX, research nurses coached intervention participants to develop a BT plan including stimulus control, modified sleep restriction, relaxation therapy, and sleep hygiene. BT plans were revised before each CTX and 30, 60, and 90 days after the last CTX and reinforced 7 to 9 days later. HEC participants received nutritional information and equal attention. Pittsburgh Sleep Quality Index (PSQI), Daily Diary, Wrist Actigraph, and Piper Fatigue Scale measures and Repeated Linear Mixed Model analysis following the Intent to Treat paradigm were used. Results Sleep quality differed over 1 years time (F [4,162] = 7.7, P < .001; by group, F [1,173] = 4.8, P = .029; and over time by group, F [4,162] = 3.3, P = .013). Pairwise comparisons revealed significant differences between groups at 90 days (P = .002) but not at 1 year (P = .052). Seven days of diary and actigraphy data did not corroborate with monthly reflections (PSQI). The night awakenings (Actigraph) pattern was significantly different by group over time (P = .046), with no differences between groups at 90 days or at 1 year. Fatigue was lower at 1 year than before.CTX; no group effects were found. Conclusion The BT group, on average, experienced significant improvement on global sleep quality compared with the HEC group, but not on objective sleep or fatigue outcomes.