I am the assigned Gen-ART reviewer for this draft. For background on Gen-ART, please see the FAQ at < http://wiki.tools.ietf.org/area/gen/trac/wiki/GenArtfaq>. Please resolve these comments along with any other Last Call comments you may receive. Document: draft-ietf-cuss-sip-uui-10 A Mechanism for Transporting User to User Call Control Information in SIP Reviewer: Joel M. Halpern Review Date: 19-May-2013 IETF LC End Date: 29-May-2013 IESG Telechat date: N/A Summary: This document is nearly ready for publication as a Proposed Standard Major issues: Minor issues: The requirements discussions for redirection and referral (second paragraph of section 3, in regards REQ-3) includes what appears to be normative requirements on redirecting devices. a) This would seem to belong in section 4 on Normative Definition. b) It would seem that there ought to be some discussion of what happens with redirecting devices that do not understand this new UUI. (I presume things work, but I don't see how.) Nits/editorial comments: In section 8.2, given that this is a WG document, should the "the authors believe" actually be "the WG believes"? Or even, given IETF rough consensus on this document, "the IETF believes"?