Cox, who has completed a number of projects for 141 Denmark, will work across a range of UK clients enhancing 141's "behaviour first" proposition.
Previously, Cox worked as in-store innovations manager at Procter & Gamble, where he was responsible for a number of projects aimed at improving retail practices. He has also advised brands and retailers on developing new in-store designs, as well as lecturing at three universities.
Cox said: "Understanding how consumers shop is the only way to create a through-the-line marketing strategy.
"My methodology is based on how consumers really shop across various retail environments so that I can recommend the correct location for products, signage and marketing material and ensure that clients get the best from their PoS material and packaging. It's all about creating pathways to purchase and reducing barriers."
Richard Church, chairman of 141 Europe, added: "Cox will give us a further insight into shopper missions, moods, motivations and purchase behaviours, enabling our clients to benefit from significantly greater promotional effectiveness."
141 is one of the world's largest below-the-line agencies with 91 offices in 57 countries and revenues in excess of $240m (£135m). In the UK, 141 has 120 staff and revenue in excess of £10m.
The companies main clients include BAT, HSBC, Boeing and Kenwood.
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