Sponsored workers with permission under the Skilled Worker, Global Business Mobility and Scale-up routes are prohibited under the Immigration Rules from changing their sponsor or the duties and responsibilities of their current job, or for their salary to reduce, unless certain circumstances apply. This Practice Note looks at when a change of employment application is required, the notification procedures for changes that do not require a change of employment application, and the consequences of failing to make a required change of employment application or notification of changes.