Berry moved to South Africa in 1952 and soon he taught himself photography and worked under the tutelage of Roger Madden, a South African photographer who had been an assistant to Ansel Adams. After some time as an amateur photographer he began photographing communities and weddings, during which time he met Jurgen Schadeberg, also a European immigrant and photographer. Schadeberg was offered a position with the new African Sunday newspaper eGoli. Schadeberg declined the offer but suggested Berry for the position instead. After working there only 10 months, the newspaper closed, and Berry began working for he Benoni City Times, but he soon became more interested in freelance work.

Berry returned to Great Britain and traveled for some time but returned to South Africa in the early 1960s and worked for the Daily Mail. Later Tom Hopkinson, previously editor of the British Picture Post, hired Berry to work for Drum magazine. He was the only photographer to capture the massacre at Sharpeville and his photographs were used in court to prove the innocence of the victims. Berry was invited by Henri Cartier-Bresson to join Magnum Photos in 1962 when he was based in Paris; five years later he became a full member. In 1964 he moved to London and began working for Observer Magazine. He has since traveled the globe, documenting social and political strife in China, Congo, Czechoslovakia, Ethiopia, Israel, Ireland, Vietnam, and the former Soviet Union. He has contributed to publications including Esquire, Fortune, Geo, Life, National Geographic, Paris-Match, and Stern.

Berry's photographs have been exhibited world-wide and some are now included in the Photographic Collection at the Harry Ransom Center, University of Texas at Austin.