I've recently worked on two different website projects both based around content management. The first was a brand new website which I built from scratch, with part of the site being content managed. The other was adding content management to an existing site which someone else had built.
The end result of both these projects is the same. The client has the ability to update the frequently changing sections of their websites themselves.
The first was TriumphHinckleyParts.co.uk - the new website. The text which doesn't change very often is just static - contact info, page headers, footer etc - there's no need to content manage these - if these ever need to be changed, I can do it manually. The list of models and all the parts though - the frequently changing parts of the site - are content managed. The client logs in and uploads photos and descriptions and updates quantities - so he controls the content of the site. These pages are database driven, so the client logs in to a control panel which I built which allows him to add/modify the model and parts details - which are stored in the database. The contents of the database are displayed on the website - so any changes he makes are instantly visible to customers.
The second project - BlackheathLuncheonClub.co.uk was slightly different in that this was an existing site built by someone else and without content management in mind. One of the key points was that the pages are html - rather than dynamic php. Now it is possible to make php run on an html page, but for some reason I couldn't get it to work on this site - so instead I had to add a new php page to serve up the content - not ideal as it meant changing the name of an existing page which has been around for a long time and may be linked to - but I redirected it to the new php page - so should be fine.
Same idea, I built a custom control panel the client can log in to and upload their photos - so they control what photos are in the image gallery - and they can decide if and when they want to change them - without waiting for their website guy to do it. Now the control panel is there, any other parts of the site they'd like to update frequently can be incorporated as well - bearing in mind that I'd have to change the page file extensions and the navigation menu as well.