I always recommend having a trial period with a potential nanny that you are thinking about hiring. In fact, I would have a trial period for two nannies. The reason being is that it is easier to compare two different candidates. What your needs are in the household, as well as, see them with your children and how they interact. Also, you want to see how they feel in the household. Is this somebody you want to supervise and manage and have in your private home? Some candidates can be completely different from their interview. You may think, "Wow, this is it. She is amazing." She's great on paper. Her interview was great. She said all the right things, and then when she comes into your home, she is missing something. There's just no that chemistry. Also, with a trial can be very helpful for logistical things like them getting to your house on time, problems or personality thing that come up. Those are the kind of tangible things that you can flush out when you figure out which candidate you should choose.