The society is working with the drinks giant as part of its ongoing Free Your Spirits campaign, through which spirits are moved from behind the counter to store shelves.
In trials with thousands of independent retailers, fitting bottles with security devices and putting them directly on shelves had driven sales up by as much as 40% in some stores in recent months, Diageo said. Now The Co-op is looking to achieve similarly stellar results.
"It's a proven growth driver," said Andy Adams, GB channel director for grocery at Diageo. "Of course you have high, medium and low-risk stores in terms of shrinkage and no one would expect any retailer in an area where there's a lot of theft to do it, but there are a lot of leafy surburban stores where they are looking at this very seriously."
A spokeswoman for The Co-op Group added: "We are continually evaluating our customer offer and this particular trial is only in a small number of our stores and one of several in-store trials that we are currently undertaking with a number of suppliers."
Diageo, supplier of big brands such as Smirnoff, Baileys and Bell's, has been running the Free Your Spirits campaign since 2009. However, The Co-op is believed to be the first multiple to have joined up. In May this year Diageo stepped up the campaign by launching a category management programme called FAST Focusing on Alcohol Sales Together.