His departure after 14 years of loyal service is not only the end of an era for him personally (after leading the station to become Campaign's TV Sales team of the Year), but also marks the sad conclusion of the Channel 5 experiment.
Williams joins the ranks of former staff members who must be contemplating what could have been had it received the investment that it deserved to build it into a successful brand supported by a family of coherent digital channels. Instead, it ended up in a fire sale, being offloaded for a knockdown price to possibly end up as a tackier version of the E! Entertainment Network.
When Channel 5 launched, it did seem to shake the cosy TV market up a little - OK, so the schedule was a bit cheap and cheerful and its premise to advertisers was largely based on cheap frequency, but it also seemed lively and more youthful than its terrestrial rivals. It put some fun back into the media sales world and it is to the credit of Williams and White, as well as Paul Curtis and Nick Milligan before them, for doing this.
Once Northern & Shell bought Channel 5 for £103.5 million in July, it's easy to imagine its then executive chairman, Dawn Airey, and programme director, Richard Woolfe, along with White and Williams, retiring to a venue not dissimilar to the depressing Bridge Cafe on The Apprentice to consider their next move. With Williams' departure, the only senior director to remain from the old regime is Jeff Ford, who has taken on Woolfe's old job.
Fun has been somewhat lacking at Channel 5 of late.
Already Richard Desmond has tried to renegotiate terms of trade with PACT and wriggle out of its contract with Sky News, and it wouldn't be beyond the realms of possibility if he also sought to at least try to come up with a new way of selling airtime that enables him to package together Channel 5 with his other Northern & Shell assets (see page 24).
Given how resistant agencies are to change, plus the potential for any changes to selling off station average price to go horribly wrong, it's no surprise that Williams decided it was time to leave.
While Nick Bampton, who joins as commercial director, is undoubtedly a talented, creative and popular salesman, the challenge of trying to find a workable sales policy that accommodates the needs of his bosses without making agencies walk away is considerable.
MTV it ain't and there are more than a few people in the industry who expect - perhaps even hope - that the Bampton/Northern & Shell partnership might also end in tears.