Previous publications have suggested that increasing the continuity of consultant working in critical care has a positive effect on patient outcomes. We introduced weekly day-time consultant working in a critical care unit and assessed the impact on mortality after one year. Two critical care units in separate district general hospitals in the same trust, with the same clinical management structure, treatment protocols and equipment, introduced changes in clinical practice at the same time during the study period. Unit one introduced a consultant work pattern of weekly working. Unit two retained the previous pattern of half-day or single full-day consultant working and acted as a control group. The mortality of all admissions and of a subgroup of ventilated admissions were compared for the year before and a year after this change. The mortality of all admissions showed a reduction in both units but this did not achieve statistical significance. The mortality of ventilated admissions in unit one showed a statistically significant reduction. There was a smaller reduction in unit two that was not statistically significant. Consultant weekly working was associated with a reduction in mortality of ventilated admissions to a general critical care unit.