[2] His first collection was attended by a London correspondent of American fashion trade magazine Women's Wear Daily (WWD), who returned the next day with colleagues from New York.
[5] In 1971, he was among eleven UK fashion designers chosen for an exhibition showcasing British talent at The Louvre – at the invitation of the director of Musée des Arts Décoratifs – entitled L'Idee de la Forme.
Other designers included Barbara Hulanicki, Bill Gibb, Jean Muir and Beatrice Bellini for Women's Home Industries – McDonnell chose to show an outfit comprising tweed tunic, tapestry-patterned sweater, blouson short pants with leggings and long doeskin cape.
[3] Writing in The Times in 1972, Prudence Glynn described Marrian-McDonnell as a rarity in London, representing what many saw as the future of the fashion retail business: "It carries a range of clothes and accessories either all designed within the firm or very tightly edited to fit in with a recognizable style.
[1][8][7] That year, McDonnell also produced a branded diffusion line for the raincoat maker Quelrayn, including embroidered cotton, velvet and seersucker coats.
[3][10] The label became well known for its woollen and jersey knitwear and its use of fine materials such as tweed and silk – although it also responded to fashion trends such as the early '70s craze for cheesecloth and calico.
[13] By 1976, Slater Walker was mired in financial difficulties, having been bailed out by the Bank of England, and abruptly withdrew from its venture with Christopher McDonnell, leaving him – as he said in 1980 – "completely broke".