The Inn had a library by the time of Henry VII, and the original building (in existence by 1506) joined the east end of the old hall, close to where it still is. It soon acquired some notable treasures. In 1514 Thomas Jakes directed that Frowyk C.J.'s illuminated statutes and 'great book of entries' should go to the Library, and in the 1550s Sir John Baker presented a remarkable year book with civilian glosses by Richard de Winchedon. None of these important early gifts survived; security was a constant problem, which even chaining the books apparently did not solve. A munificent gift which does survive intact, however, is the collection of historical manuscripts bequeathed by William Petyt (d. 1707). The manuscripts of the Hon. Daines Barrington (d. 1800) include an early copy of Littleton and a brief for the prosecution of Mary, Queen of Scots.

The Library tower after the first air raid, 19 September 1940.

The accommodation for the Library has had a chequered history. The old building used by Coke and Selden was burned down in the Great Fire of 1666, and its replacement was blown up in 1678 in an endeavour to stop the spread of another fire. There was another rebuilding, this time in gothic style, in 1835. The Victorian building (1870), designed by Smirke in the same perpendicular style as the hall, was remarkable for its distinctive clock-tower surmounted by a pegasus weather-vane. That building was destroyed in 1941, with the loss of about 40,000 volumes, though the manuscripts and rarest books had been removed to the country and saved. A temporary Library was soon established in No. 1, King's Bench Walk, and the new library was opened in 1958. The present Library houses over 100,000 volumes, and grows at the rate of over 1,000 volumes a year.

Tanfield Court, looking south. Drawn by Henry Hodge, 1880.

Among the treasures now kept in the Library (besides the printed and manuscript books) are four superb painted miniatures showing the courts in Westminster Hall in around 1460; the gold collar of SS. worn from 1824 to 1844 by Chief Baron Alexander and Lord Abinger; a collection of serjeants' rings started by Sir Harry Poland; and a triptych containing the old statutes of Clifford's Inn on vellum. The Inn also has an extensive collection of domestic archives, including acts of the Inn's parliament (from 1505), admissions (from 1547), account books (from 1606), chambers records (from 1615), and bench table orders (from 1668).