Under section 109(1) of the Equality Act 2010 (EA 2010), an employer is liable for acts of discrimination, harassment, and victimisation carried out by its employees in the course of employment: “[a]nything done by a person (A) in the course of A’s employment must be treated as also done by the employer.” Section 109 further states that “[i]t does not matter whether that thing is done with the employer’s … knowledge or approval.” However, under section 109(4) EA 2010, an employer has a defence if it can demonstrate that it “took all reasonable steps” to prevent the employee from carrying out the act of discrimination. When considering an employer’s defence that it took all reasonable steps to prevent an employee from discriminating against another employee, a tribunal will examine how effective the steps were likely to be when they were taken and how effective they proved to be in practice. The decision of Allay (UK) Ltd v Mr S Gehlen looks at the scope of this defence.