The Quality and Outcomes Framework (QOF) is a system for the performance management and payment of general practitioners (GPs) in the National Health Service (NHS) in England, Wales, Scotland and Northern Ireland. It was introduced as part of a new general medical services (GMS) contract in April 2004, replacing various other fee arrangements. Aims and mechanisms The QOF was part of a revised contract for GPs. It was intended to improve the quality of general practice and was part of an effort to solve a shortage of GPs. The QOF rewards GPs for implementing "good practice" in their surgeries. Participation in the QOF is voluntary for each partnership, but for most GPs, under the present contract, the QOF is almost the only area where they can make a difference to their income. Almost all participated. Most practices got, and still get, a significant proportion of their income through the QOF. In the 2004 contract the practice could accumulate up to 1050 'QOF points', depending on level of achievement for each of the 146 indicators. The criteria are grouped into 4 domains: clinical, organisational, patient experience and additional services. The criteria are designed around best practice and have a number of points allocated for achievement. At the end of the financial year the total number of points achieved by a surgery is collated by the QMAS or other system which then converts the points total into a payment amount for the surgery. The formula includes the number of patients and in particular the numbers diagnosed with certain common chronic illnesses; the clinical element awards points for achieving specified clinical "indicators". A typical clinical indicator would be the proportion of patients with coronary heart disease who had cholesterol measured in the financial year, or the number of patients with depression who have answered a standard questionnaire on severity. Organisational indicators include such things as the availability of practice leaflets and practice staff education. In the organisational domain the value of points was proportional to the number of patients registered with the practice. In the clinical domain the value of points was further modified by the prevalence of that condition in the practice – this was measured as the square root of the ratio of the national prevalence. For a typical practice the payment was £77.50 per point in 2004/5 and £124.60 in subsequent years. The QOF system is supervised and audited by