<P> A National Health Service trust is an organisation within the English NHS generally serving either a geographical area or a specialised function (such as an ambulance service). In any particular location there may be several trusts involved in the different aspects of healthcare for a resident . </P> <P> NHS trusts were established under the National Health Service and Community Care Act 1990 and were set up in five waves . Each one was established by a Statutory Instrument . </P> <P> The trusts are not trusts in the legal sense but are in effect public sector corporations . Each trust is headed by a board consisting of executive and non-executive directors, and is chaired by a non-executive director . There were about 2,200 non-executives across 470 organisations in the NHS in England in 2015 . Non-executive directors are recruited by open advertisement . All trusts (Foundation trusts and those which have yet to reach foundation trust status) are regulated by NHS Improvement . Board members are, from November 2014, subject to a Fit and proper person test . </P> <P> All trust boards are required to have an audit committee consisting only of non-executive directors, on which the chair may not sit . This committee is entrusted not only with supervision of financial audit, but of systems of corporate governance within the trust . Hospital board members have a duty to act on signals of poor performance on quality and safety data, and yet many of the papers presented to them have been found to be lacking good data visualisations . </P>

How many nhs trusts are there in england