The contract caterer joins 450 other employers in the forum, which allows organisations to work with Stonewall, and each other, to promote lesbian, gay and bisexual equality in the workplace and access best practice and research.
Sharon Kyle, head of employee engagement and diversity at Sodexo, which employs 43,500 staff in the UK and Ireland, said she was "very pleased" to join forces with Stonewall.
"Having worked with them before, I am confident that the support, advice and the sharing of other organisations' best practice will be invaluable in helping us ensure we meet the needs and expectations of our lesbian, gay and bisexual employees, clients and customers," she said.
As part of its commitment to diversity, Sodexo is already a member of groups including the Employers Forum on Age, Employers Forum on Disability, Race for Opportunity and Opportunity Now.
By Daniel Thomas
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