The present document is the Stage 2 specification for the security requirements@ security architecture@ security features and security mechanisms for the Presence Service@ which includes the elements necessary to realise the requirements in TS 22.141 [2] and TS 23.141 [3]. As far as SIP-based procedures are concerned@ this specification refers to TS 33.203 [4]. The main content of this specification is the security for the Ut reference point@ which is HTTP?Cbased@ as applied in presence services. The present document includes information applicable to network operators@ service providers and manufacturers.