Hi all: I've just got back from my summer break, so this review is a little late - sorry about that. I have performed an Operations Directorate review of draft-ietf-ecrit-ecall-21 "This document describes how to use IP-based emergency services mechanisms to support the next generation of the pan European in- vehicle emergency call service defined under the eSafety initiative of the European Commission (generally referred to as "eCall"). eCall is a standardized and mandated system for a special form of emergency calls placed by vehicles, providing real-time communications and an integrated set of related data. This document also registers MIME media types and an Emergency Call Additional Data Block for the eCall vehicle data and metadata/control data, and an INFO package to enable carrying this data in SIP INFO requests. Although this specification is designed to meet the requirements of European next-generation eCall, it is specified generically such that the technology can be re-used or extended to suit requirements across jurisdictions." This draft documents the next-generation (SIP-based) eCall system, and registers all the parameters it uses. It's well-written and fairly easy to understand. Lots of partiular cases are noted as "outside the scope of this document", so users of this document will need to read and understand all of its normative references. Lots of XML elements defined "for extensibility," systems that use these will need to be well-documented. From the Operations point of view, users of NG-eCall will need to make sure that any systems they deploy are fully compliant with this draft. and all of its normative references. The draft notes (in section 3) that there will be a transition period from the existing eCall system to NG-eCall, but that transition arrangements are outside the draft's scope. Current deployers of eCall will need to work out their own transition arrangements! Only one nit: Section 14 uses [TBD: THIS DOCUMENT]; why not just "this document" - the way it's written it looks like a references to the document itself! Cheers, Nevil