The present document specifies generally applicable policy and security requirements for Registered Electronic Mail Service Provider (REMSP), including the services they provide. The present document is applicable to: - The policy and security requirements of REMS and EU qualified REMS providers. - The general and security requirements of REMS and EU qualified REMS. The present document does not specify interconnection requirements. The present document aims to cover the common and worldwide-recognized requirements to address electronic registered delivery in a secure and reliable way. Particular attention is paid to the Regulation (EU) No 910/2014 [i.1]. However, the legal effects of services implemented according to the present document are outside the scope of the present document.