Cottrell's own translation of The Cherry Orchard, starring Lila Kedrova and Patrick Wymark, transferred to the Queen's Theatre in London in 1967.
[3] Cottrell translated Georges Feydeau for the Prospect Company, and, with Lance Sieveking, adapted E. M. Forster's Howards End and A Room with a View.
From 1975 to 1980, Cottrell was Director of the Bristol Old Vic Company, where his notable productions included The National Health, Hedda Gabler, As You Like It, A Doll's House, and A Midsummer Night's Dream.
His work at Nimrod included The Winter's Tale, Les Liaisons Dangereuses, All's Well That Ends Well, Wild Honey, The Merchant of Venice, and Arms and the Man.
[4] For the Sydney Theatre Company, Cottrell has directed Lettice and Lovage and Vita and Virginia, both starring Ruth Cracknell.
Cottrell's recent productions include Ying Tong, A Walk with the Goons, and Travesties for the Sydney Theatre Company.