This has been discussed before I think. Some countries (e.g. US) require you to enter with their own passport if you have one. I should think your colleague would do well to:
Enter UK on her UK passport
Leave UK on her UK passport
Show Gate Agent Canadian passport
Enter Canada on her Canadian passport
In effect, she would have never left home!
If I am incorrect, would someone please correct me?
Last edited by The Ivory Actuary; Jul 17, 2008 at 1:08 pm
Reason: fixed inexact & incorrect information