On This Month at Sotheby's, host Kelsey Leonard shares some truly interesting stories. All eyes are on New York this month for The New York Sales, an exciting group of auctions presaging the spring season. Leading the way is The Mo Ostin Collection Evening Auction, a selection of Modern and Contemporary masterpieces from the personal collection of the late industry mogul. Next, one of the most renowned collections of 20th-century photography in the world, The Pilara Family's treasury of photography is being presented in dedicated sales on 1 and 2 May, in Pier 24 Photography from the Pilara Family Foundation Sold to Benefit Charitable Organizations. On 12 May, Geneva's Luxury Week returns to the Swiss City with a series of live sales featuring dazzling gems, watches, handbags and much more. Finally, join art historian and museum director Tim Marlow as he brings us his pick of exceptional new exhibitions taking place around the world.