Which employees are "shop workers" for the purpose of the right to opt out of Sunday working?

A "shop worker" is an employee who, under their contract of employment, is or may be required to do shop work.

"Shop work" means work in or about a shop on a day on which the shop is open for the serving of customers.

The term "shop" includes any premises where any retail trade or business is carried on (such as department stores, supermarkets, high street shops, off-licences, barber shops, hairdressing premises, hire service shops and auction rooms), but does not include hotels and catering businesses (eg restaurants, cafeterias, public houses and take-away establishments) or the sale of programmes, catalogues and similar items at theatres and places of amusement.