The aim of this prospective cohort study was to examine the effectiveness of a low intensity outpatient cognitive rehabilitation programme for patients with acquired brain injury in the chronic phase. Twenty-seven patients with acquired brain injury (i.e., stroke, traumatic brain injury, subarachnoid haemorrhage; 52% male) with a mean age of 49.5 (SD 9.2) years and 25 relatives with a mean age of 48.8 (SD 8.8) years were recruited to the study. Mean time since injury in the patient group was 1.9 years (SD 2.0). The group programme consisted of 15 weekly sessions of 2.5 hours and included cognitive strategy training, social skills training, and psycho-education. Patients also received homework. Relatives were invited to attend twice. Repeated measurements were taken: prior to treatment (baseline, T0); directly after treatment (T1, 21 weeks); and at follow-up (T2, 45 weeks). Primary outcome measures were individualised goals (GAS), cognitive failures (CFQ), and quality of life (SA-SIP). Patients did improve significantly on individual goals (p < .05) between T0 and T1 and the level of attainment remained stable between T1 and T2. Goals were mostly set in the cognitive and behavioural domains. There were no significant differences between the measurements (T0-T1-T2) on the CFQ and the SA-SIP. The programme had a positive effect on the individual goals set by the patients. However, this did not result in a higher participation level or a better quality of life. This may be due to the low intensity and short duration of the programme.