Statutory Instruments (SIs)
Statutory instruments are the most common form of secondary (or delegated) legislation.
The power to make a statutory instrument is set out in an Act of Parliament and nearly always conferred on a Minister of the Crown. The Minister is then able to make law on the matters identified in the Act, and using the parliamentary procedure set out in the Act. SIs may follow affirmative or negative procedure, or have no procedure at all, but which to use is fixed by the Act.