My company is quite small, and we do not use any Change Management. We are part of the way there by requiring the requests for changes to be logged in our helpdesk, but that isn't done in such a way that there's any real trail to the actual changes.

There's so much to do and so little time, it's hard to initiate something like this by choice. On the other hand, it would be better to do it by choice than to have a situation where a director of the company gets involved and asks why things weren't better documented/controlled.