Estimates of patients attending with conditions deemed non-urgent or inappropriate for accident and emergency services vary widely, from 6 to 80%. Previous research suggests that general practitioners (GPs) working in emergency departments can reduce referral rates, diagnostic testing, the proportion of patients who become emergency hospital admissions, and inappropriate attendances. However, little of this previous research is recent and new models of care for GPs working in emergency departments have now been developed, which remain to be evaluated. In this paper, we describe an integrated urgent care model, which was commissioned by NHS Hammersmith and Fulham in 2009 to manage the rising number of urgent attendances at local hospitals and its associated evaluation. The evaluation will include examining the effect of the system on outcomes such as utilization of diagnostic tests and effect on unplanned hospital admissions. If the new model of care is shown to be both clinically effective and cost-effective, the model and the proposed plan of evaluation will also be helpful to other areas that are considering the introduction of similar models of GP-led urgent care.