This is the SECDIR last-call review, intended to be input to the Security AD's. Ready with nits. The Security Considerations and Privacy Considerations are short, but they seem to reasonably refer to already-published documents. Following are nits I noticed. Abstract "a number of new iCalendar properties and components" -> "a new iCalendar component and a number of properties" Maybe stike "iCalendar" Sec 1, STRUCTURED-DATA. In my opinion the confirmation code would be the most useful new info :) Sec 1, SOURCE Is it redefined or extended? Sec 2, para 2. "In a break with this 'tradition' ..." --> "Breaking with this practice, ..." Sec 3, "When a calendar client receives a calendar component" Should the second calendar be CALENDAR? Should the first be "iCalendar"? Sec 3.1.1, uppercase "vcard"? Sec 3.1.2.1 "non of which" --> "none of which" Sec 4 Perhaps add a sentence saying where this syntax is defined. Is this the complete iCalendar spec or is it just changing a few things? Sec 5.1, etc "as laid down in" Is kind of informal wording. Sec 6, the notation has "value=URI" but the example has "URL" (Sec 7.3, etc., uses URI in both parts) Sec 10, "applications using" Is "acting on" better?