[5] From 1933 to 1936 he worked in advertising agencies, and in 1936, together with three friends, he invested in a listings magazine, London Week, later called What's On.

[4] Usborne abandoned publishing and moved back into advertising, working for the large London Press Exchange.

Usborne was remembered for giving "warm, cheerful and avuncular encouragement to young and inexperienced budding writers".

[7] By the late 1940s the magazine was suffering from falling circulation and rising costs; the final issue was published in March 1950.

Usborne then worked on the Leader Magazine before returning to teaching as a master at St Paul's School, where, one pupil recalled, he "taught my youthful generation how to read poetry, to learn to love it and even to write it".

[n 1] Usborne continued to write for Punch during the succeeding decades; his final contribution was a 90th-birthday tribute to P. G. Wodehouse, published in October 1971.

This work sought to reappraise the adventure stories of the British authors Dornford Yates, Sapper, and John Buchan.

E. V. Knox praised "the delightfully satirical way" in which Usborne summed up the characters and exploits of the heroes,[14] Philip Toynbee called the book "a jeu d'esprit that will give great pleasure … a fine piece of gentle but sustained irony",[15] and Punch found it "enjoyable and absorbing to read besides being penetrating criticism".

[20] Although Wodehouse praised the book when it was published, he found its author – whom he called "a certain learned Usborne"[21] – too inclined to bring in biographical details rather than concentrating on the works as agreed.

[24] He thought Usborne paid too much attention to the school stories from Wodehouse's very early career, when, in his words, "I was hardly articulate".

It consists, like its predecessor, of ten main sections – an introductory biographical chapter setting Wodehouse and his works in context, and chapters on the school stories; Psmith; Ukridge; Lord Emsworth and Blandings; Uncle Fred; the light novels; the short stories; Bertie Wooster; and Jeeves.

Reviewing it, The Philadelphia Inquirer called Usborne "the world's leading Wodehouse expert" and recommended readers to "grab" the book.

[35] Between 1979 and 1996 Usborne adapted some of Wodehouse's stories for broadcast on BBC Radio, beginning with a serialisation of Jeeves and the Feudal Spirit (1979), starring Michael Hordern as Jeeves and Richard Briers as Bertie Wooster; in 1985 Usborne's adaptations of seven Blandings short stories were broadcast and in 1987 he adapted the novel Summer Lightning, followed by Heavy Weather (1988), Pigs Have Wings (1989) and Galahad at Blandings starring Richard Vernon as Lord Emsworth and Ian Carmichael as Galahad Threepwood.

[6] Usborne's only non-Wodehouse book after the publication of Wodehouse at Work was A Century of Summer Fields (1964), "a collection of tributes, reminiscences and other items, by old boys, masters, friends and critics" (including a poem by C. Day Lewis) edited by Usborne at the request of the governors of the school.