People in remote Aboriginal communities in the Northern Territory have greater morbidity and mortality than other Australians, but face considerable barriers when accessing hospital-based specialist services. The Specialist Outreach Service, which began in 1997, was a novel policy initiative to improve access by providing a regular multidisciplinary visiting specialist services to remote communities. It led to two interesting juxtapositions: that of 'state of the art' specialist services alongside under-resourced primary care in remote and relatively traditional Aboriginal communities; and that of attempts to develop an evidence base for the effectiveness of outreach, while meeting the short-term evaluative requirements of policy-makers. In this essay, first we describe the development of the service in the Northern Territory and its initial process evaluation. Through a Cochrane systematic review we then summarise the published research on the effectiveness of specialist outreach in improving access to tertiary and hospital-based care. Finally we describe the findings of an observational population-based study of the use of specialist services and the impact of outreach to three remote communities over 11 years. Specialist outreach improves access to specialist care and may lessen the demand for both outpatient and inpatient hospital care. Specialist outreach is, however, dependent on well-functioning primary care. According to the way in which outreach is conducted and the service is organised, it can either support primary care or it can hinder primary care and, as a result, reduce its own effectiveness.