Purpose: Studies of workplace equality have often questioned the effectiveness of employers’efforts to tackle employment disadvantage. This article is concerned with the role that civil society organisations (CSOs) play in promoting equality at work. The main aims of this article are to: examine the role played by CSOs in promoting equality and challenging disadvantage at work through engaging with employers; characterise the ways in which they operate as mediating agents; and to reflect on the implications of CSO interventions for understanding how the process of mediating workplace equality operates. Design / methodology / approach: The paper uses interview data from a study of the work and employment-related activities of CSOs operating in the UK, and was undertaken during 2007 and 2008. In-depth interviews were conducted with key respondents from a carefully selected sample of CSOs. Findings: It is found that there is a marked emphasis that many CSOs place on tackling equality issues by engaging positively with employers. Originality / value: The paper examines the role played by CSOs in tackling inequality and disadvantage in work and employment by engaging with employers, characterising how they operate as mediating agents.