This Practice Note considers the meaning of transfer of an undertaking, transfer of a business, and transfer of part of an undertaking or business, within the meaning of regulation 3(1)(a) of the Transfer of Undertakings (Protection of Employment) Regulations 2006 (TUPE 2006), SI 2006/246. It examines the key elements of economic entity, retention of identity, ie whether the economic entity retains its identity after the transfer, organised grouping of resources, whether a single employee can be an undertaking, the need for stability, ie a stable economic entity, and illegal purposes. It also examines how to assess whether a relevant transfer takes place, transfers effected by a series of transactions, the date of transfer, share sales, intra-group transfers, the ‘going concern’ test (Spijkers), temporary cessation of activities, the transfer of part of a business or undertaking, fragmentation, the need for the undertaking to be situated in the United Kingdom (UK) and public administrative authorities. Relevant transfers under the Transfer of Undertakings (Protection of Employment) Regulations 2006, SI 2006/246 (TUPE 2006) are: • business transfers—involving the transfer of an undertaking or