My dog has his pet passport but he has not used it yet. We are hoping to go to the World show in paris in July and was hoping for some clarity with the requirements fore leaving the UK and before re-entering?
Thanks in advance.

Nothing to do before, except you might want to check the microchip is working.  Just pop to your vets and ask if there's a nurse available or even the receptionist who can scan it to check it's working. 

When you're coming back, you need to visit a vet not less than 24 and not more than 48 hours before leaving for the UK.  This is for the tick and tapeworm treatment.  The tick treatment is usually Frontline.  Some vets give a jab for the tapeworm, but you can take your own Droncit tablets and say you want to use those instead.  The vet has to stamp the Pet Passport and write the time and date of your visit there. 

When you get to the port or chunnel, head for the paw print sign on a yellow background.  This is the Pet Passport booth.  They will check your passport and scan for the microchip. 

That's it. 

The hardest bit is finding and booking a foreign vet.  Recommendations are good.  I would also recommend this service, which will take care of it all for you - you just tell them when you are travelling and where you will be 24-48 hrs before and they will find and book you a vet who knows what they're doing:

http://www.dogsaway.co.uk/

Excellent, thankyou very much.

There should be vets at the show doing the worming and Frontlining. The timing is the thing to work out -if doing it at the show you can't go home for another 24 hours, if you're doing a super quick visit you may be able to have it done by a vet in the UK BEFORE leaving if it still makes less than 48 hours when you come back.

After you have visited the Vet just ensure that the passport has all the necessary pages signed with the product used, the date and time of treatment and the signature and stamp of the Vet. It only needs the Vet to miss one of the pages or some of the info off and you will have problems at the passport control.

Yes, and vets do miss bits off - our vet forgot to write the time in - just left it blank.  We had paid and returned to our car, and I checked both passports and noticed this - luckily we were still there and I could go back and get them to fill it in.  Very relieved we didn't discover that at Passport control.

Thankyou for all the replies....now all i have to do is try and some sense of the World Dog Show (paris) website, where it is supposed to have an English version but doesn't.