During the middle ages there was great rivalry as to the precise order of precedence of the livery companies.  It is recorded that certain processions broke up as liveries fought for what they thought was their rightful position.  It was more than just seniority at stake as the more senior the Company the more power it was deemed to possess.

In 1515, the Court of Aldermen of the City of London settled an order of precedence for the forty-eight livery companies then in existence.  This was very much based on the companies' economic or political power.  The antiquity of the companies was not a major consideration. It is of interest that the senior companies are predominantly retail trades and wholesalers.  Companies of involved in manufacturing clearly had less influence in the City by the beginning of the sixteenth century.

The first twelve livery companies are known as the Great Twelve. There are now 108 livery companies. There are few arguments about precedence today and new companies are added in an orderly fashion.

The Merchant Taylors and the Skinners have always disputed their precedence, so once a year (at Easter) they exchange sixth and seventh place. This arrangement dates from Lord Mayor Billesden/Billesdon promulgating this compromise in 1483. This alternation is often cited as the souce of the phrase 'at sixes and sevens.'  However the first use of the phrase is known from before, Chaucer certainly used it over a century before, so like a number of other City myths such as the right of liverymen to keep sheep in the City and to use London Bridge for the purposes of moving livestock it is best dealt with caution.

The Great XII comprise:
1.The Worshipful Company of Mercers (General merchants)
2.The Worshipful Company of Grocers
3.The Worshipful Company of Drapers (Wool and cloth merchants)
4.The Worshipful Company of Fishmongers
5.The Worshipful Company of Goldsmiths
6.The Worshipful Company of Merchant Taylors (Tailors) (alternates with the Skinners)
7.The Worshipful Company of Skinners (Fur traders) (alternates with the Merchant Taylors)
8.The Worshipful Company of Haberdashers
9.The Worshipful Company of Salters
10.The Worshipful Company of Ironmongers
11.The Worshipful Company of Vintners (Wine merchants)
12.The Worshipful Company of Clothworkers

Most of the privileges of the Great XII have been abolished in the last century. one that caused particular problems was that the Lord Mayor, if he were not a member of the Great XII, had to join one of them before election.  This caused all sorts of problems as to who would bear the very considerable costs the mayoralty then entailed.