In dealing with civil cases, the Court of Appeal normally consists of Lords Justices of Appeal, who are presided over by the Master of the Rolls, who performs a curious role in that, in addition to being the senior judge of the Court of Appeal, he also has supervisory powers over solicitors.
Lords Justices of Appeal must be barristers of at least fifteen years’ standing, or have been High Court judges for at least on year, and are appointed by the Crown on the recommendation of the Prime Minister.
A normal court consists of three judges, but under certain circumstances there may be a court of only two. Where a point of law of great importance or difficulty is involved, there may be a ‘full’ court of five judges. In theory there is no difference between a court of three and a court of five – judgment is unanimous or by a majority – but where a precedent is established by a full court it commands greater respect and is less likely to be overruled.
There are 18 Lords Justices of Appeal, and as High Court judges also sit in the Court of Appeal, there may be nine or ten courts of appeal sitting at any one time.
The Lords Justices of Appeal also form the nucleus of the Court of Appeal when it is dealing with criminal cases, but in this capacity they are presided over by the Lord Chief Justice of England, and are supplemented by High Court judges of the Queen’s Bench Division as business requires. The Lord Chief Justice must be a barrister of at least fifteen year’ standing, and he is appointed by the Crown on the recommendation of the Prime Minister.
A Lord Justice of Appeal may sit in the High Court, exercising the powers of the Court of Appeal judge but only on rare occasions does this happen, as the Lords Justices of Appeal are more than fully occupied with the work of the Court of Appeal.
The Supreme Court Act 1981 provides that one of the ordinary judges of the Court of Appeal may be appointed as Vice-President of the Court of Appeal as a whole, or one may be appointed as Vice-President of the Civil Division and another as Vice-President of the Criminal Division to preside in the absence of the Master of the Rolls or the Lord Chief Justice.
Lords Justices of Appeal are not, despite their title, members of the House of Lords. They are in fact knights, so that in private life they are known as, for example, Sir Thomas Robins. Such a person in his official capacity would be known as Lord Justice Robins, and in legal literature this is abbreviated to Robins L.J. (plural L.JJ.)

See Also:
Lords of Appeal in Ordinary
House of Lords
House of Lords: Final Appeal
Function and Status of Judges
Judicial Independence and Immunity