The furore resurfaced last week when high-profile authors including Ian McEwan, Yann Martel, Graham Swift and AS Byatt boycotted the London Book Fair, also run by Reed.
In a letter to The Times Literary Supplement, the authors wrote: 'We are appalled that our trade should be commercially connected to one which exacerbates insecurity and repression.' They went on to describe the defence exhibition as the company's 'crown jewel'.
Protesters complained that the arms fair involved representatives from countries with questionable human rights records.
Luther will work to ensure Reed is adequately prepared for demonstrations and alert to sensitivities across its portfolio of shows. Reed runs 460 exhibitions in 38 countries for industries such as bioscience, travel, cosmetics and jewellery.
Reed Exhibitions CEO Alistair Gornall said: 'We chose Luther after an extended period of working with the agency on a project basis around individual shows. Now we will develop contingency plans and strengthen our media teams across our portfolio.'
Gornall took up his present role in June 2004 after a 20-year career in the PR industry. He is a founder of Consolidated Communications and Scope Communications.
The Luther team is led by associate partner Jonathan McShane, with support from partner Mike Granatt.
The London Book Fair took place at ExCeL in London's Docklands, the same venue used for the biannual arms fair. DSEI features around 300 companies pitching their wares – their industry is thought to be worth $1 trillion a year.