Once you have a nanny applicant or, preferably, a handful of applicants, the evaluation process begins. You’ll want to thoroughly check a candidate’s references and background, as well as pay her for a day of trial baby-sitting before you leave your child alone with her.

Begin by screening candidates over the phone with basic questions: What is her experience with infants and toddlers? Is she trained in CPR? Does she have a driver’s license and a car? What language is she most comfortable with?

If she’s not fluent in English, ask if there’s an English-speaking relative or friend who can translate these questions. If your potential caregiver isn’t a U.S. citizen, tell her you’ll need to see a green card or social security number.

It’s important to be clear about your expectations. Think carefully about your current and upcoming childcare needs and whether you’d like to include light housekeeping, laundry and meal preparation as part of her responsibilities. You may want to specify, however, that childcare comes ahead of other tasks.

If you like what you hear from a candidate, start calling references. Previous employers are a goldmine of information, so don’t be satisfied with generalizations such as, “She’s terrific. The kids loved her.” Ask the employers what they liked most about the nanny and what they were least satisfied with. Would they hire her again?

Schedule interviews with the best candidates and arrange to talk for 20 minutes without your child present, so you can concentrate. Greet her warmly and establish an atmosphere of mutual respect. Ask open-ended questions and encourage her to tell stories about her nanny experiences. Here are sample questions:

1. Describe the personalities of the children at your previous job. What was the most fun about working with them? What was tricky?

2. What activities do you like to do with an infant? With a 1-year-old or a toddler?

3. Have you ever had to handle an emergency? What did you do?

4. How do you deal with a tantrum? What are your feelings about discipline?

For the second part of the interview, introduce her to your child and observe how the two of them interact. If your gut feeling is positive, pay her to baby-sit for a day when you can be at home but in the background. This is a significant test. If she passes, you’re probably ready to hire. At this point, many families buy additional peace of mind by paying an agency to perform a background check.

Assuming the background check comes back clear, there’s one more consideration: Are you going to withhold taxes from her check? As far as the federal government is concerned, a nanny working in your home is your employee. If you paid the same childcare provider more than $1,500 in 2006, you’re responsible for paying Social Security, Medicare and unemployment taxes. An Internet search for “nanny taxes” will bring up companies that can determine what you owe.

Finally, draw up a written agreement that includes work hours, pay and optional benefits, such as a one-week paid vacation a year. This is the beginning of a relationship that could significantly add to your family’s well being. Most nannies become quite devoted to their charges and bring a warm and loving presence into your home.