OK, it looks like the OP is in Great Britain so, I'd say ignore all the folks that want a one page resume. As someone who's spent time in the US & UK the obsession with a single page resume is a singularly American issue from my experience. Unless applying to a US company don't worry about going over one page.
You cannot write a CV that pleases everybody. I've had things on a resume that someone that hired me really like. Then I've had that CV/resume reviewed by an 'expert' in the field and the first thing they did was take that thing off.
It's compounded by the fact that your CV/resume often has 2 audiences, HR and then Technical/Management. Actually, sometimes it can be 3 audiences at Technical and Management may have different ideas.
What MikeHollaran says is very good, if the first section grabs the readers attention then you probably have an in.
I would say that with few exceptions 2 pages is a maximum so don't go over that, leave stuff out if necessary or even better find a more concise writing style.
My personal pet peeve, is that a lot of advice these days says to give examples, not just general descriptions of what you've done. Trouble is I've always been a bit of a 'jack of all trades' so by the time I put examples of all the wonderfull things I've done for each job duty I have trouble sticking to 2 pages, let alone 1.
Customizing a resume can help with this as you tune it to the job you're applying for, however this takes a lot more time.
And of course all this is jacked up by any online submittal process that at best usually strips any formatting from your resume, at worst requires you rewrite the entire thing in their preffered format in a way that it's almost impossible not to make it too long and/or miss stuff out.
(excuse my mixed use of resume & CV, I just couldn't keep it straight;-))
Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484