A Touch of Class



An Inside View of the CSS Working Group at W3C

This series of posts is about how the CSS Working Group operates in reality.


The CSS Working Group regularly communicates at three different levels:

Mailing Lists

Technical discussion on the CSS specs takes place on the www-style mailing list; discussion on the CSS test suites takes place on public-css-testsuite. Both of these lists are (a) public and (b) archived. Communicating through these lists ensures that both members and non-members can participate and contribute, and ensures that the rationale for our decisions is archived for future reference.

While not everyone reads every post on www-style (it's a very high-traffic mailing list), every CSS WG member is expected to follow the list. This mailing list is where proposals are hashed out, feedback processed, spec questions answered, and typos reported and fixed.


The CSS WG meets virtually once a week for an hour. Each telecon has a designated chair (either Daniel Glazman or Peter Linss) and a designated scribe. The scribe is responsible for taking minutes, which are then formatted and posted to www-style for archive and further comment. Although the official record of the meeting is the one posted to the mailing list, a summary is posted on the CSS WG Blog and cross-linked from Twitter.

CSS WG telecons are multi-modal: although the main discussion threads over the telephone bridge, we use an IRC channel in parallel. It's used by the scribe for minuting, and by the members to pass links, code fragments, wording proposals, corrections to the minutes, side comments, and snarky jokes. Several IRC bots help with logging the channel (RRSAgent), managing the phone bridge (Zakim), and tracking action items (Trackbot).

Here is an example of telecon minutes and the IRC log from which it was derived.


The CSS WG meets in person (“face-to-face”) 3-4 times a year. These meetings are hosted by one or another of our Member companies, in a conference room at one of their office facilities. Since the CSS WG has a global membership, meeting locations are split: about half in the US and half in Europe or Asia. F2F meetings are typically 3 days long, from 9am to 6pm (or beyond). Peter and Daniel take turns chairing during an F2F, and CSS WG members take turns scribing throughout the meeting. As with telecons, IRC is used as a backchannel, and the minutes are posted to www-style.

To better coordinate with other groups at W3C, each year one of the CSS WG's F2F meetings is scheduled to be at W3C's annual Technical Plenary and Advisory Committee Meetings (TPAC). During this week-long conference, W3C's groups can all meet in the same place at the same time, allowing easier cross-WG interactions. The CSS WG will often schedule joint meetings with other groups at TPAC, such as the SVG WG and the I18N WG. In addition to formal joint meetings, informal interactions with other W3C members during breaks and in the evenings help create links across W3C's many Working Groups.

F2Fs give the CSS WG a chance to work through complicated, vague, and/or conflict-ridden issues in person. We can take advantage of having everyone in the same room, focused on the same thing, and able to use a whiteboard. They're also a chance for everyone to get to know each other better: one of the strengths of the CSS WG is that our members all have good working relationships with each other.

The CSS WG also has two back-channels:


The CSS WG's IRC channels are public, but fairly quiet. Although there is the occasional exchange during off-hours, they are mainly used during the telecons and F2Fs. Krijn Hoetmer and Peter Linss have set up continuous logging for the main channel. During meetings, W3C's RRSAgent also logs to the W3C server; these logs are typically posted along with the formatted minutes. Outside of meetings, discussions in the IRC channel are unofficial.

Internal Mailing List

Historically, the internal mailing list was used for technical discussion among the CSS WG members, so its archives include technical records prior to the CSS WG's transition to a public group. However, these days it is restricted only to administrative and process-related discussion: coordinating meeting times and locations, crafting meeting agendas, spec-publishing mechanics, drafting official liaison statements to other standards groups, revising the charter and the like. Sometimes a discussion on the internal list waxes technical; inevitably someone notices, and the discussion is forwarded to www-style for continuation. However on the rare occasion that the group needs to handle W3C Member-confidential information, any related technical discussion will remain on this internal list.

We also have several servers for hosting materials:

In addition to the official CSS specifications, this server hosts CSS Working Group Home Page and CSS Working Group Blog.
This revision-tracked server hosts the semi-official CSS editor’s drafts in CVS. In addition to hosting live copies of the latest, this server can also show old revisions, diffs between revisions, and change logs through its cvsweb interface.
This server hosts the CSS WG Wiki, where we plan meetings, track issues, post test suite guidelines, and generally document other useful things.
This server hosts the CSS test suites and associated systems.

In addition to WG-level discussions, co-editors are also expected to keep in regular communication with each other. Communication styles will vary here; below are some examples from my personal experience:

Next up: CSS WG — Making Decisions