My advice for the best experience is NOT to go through an agency. They are, understandably, businesses whose primary objective is to make money, not happy matches. The best nannies and maids are found by word-of-mouth--families leaving the country and looking to find good places for their maids. Advertising at your children's school, place of work and amongst friends is the best approach. It may take longer, but you'll be happier with the result.

Once you have a good maid, treat her well. My kind are often accused of "spoiling" our maids by over compensating them and treating them as equals, but I have to say I never worry about leaving my vulnerable children alone with her as I know that she is happy and unresentful towards my family.