Despite being a prolific draughtsman, fewer than 20 paintings by Leonardo survive. But which were his greatest hits?

How did spies, curators, and an army of art handlers save some of the world's most important artwork? An excerpt from the new book The Art Spy, reveals the amazing truth.

Plus, some clarity on the much-discussed new partnership in town, Uffner and Liu.

Museum-quality masterpieces, rediscoveries and record-setting sales defined the fair’s return to the Park Avenue Armory.

Starting in the 1930s, the three artists behind PaJaMa captured their unconventional relationship in surreal images that ...

Ahead of the big spring auctions in New York, Observer spoke with Christie’s head of the marquee 21st Century Evening Sale.