Sandra Scarr, Commonwealth professor of psychology at the University of Virginia, has some reassuring words, as well as good advice, for the hundreds of thousands of mothers who are putting young children in day care: "It is a myth," she says, "that the caretaker has to be biologically related to the children. What is important is that the care be related to the development of the children and their individual needs."

Scarr brings impressive academic and personal credentials to the entire issue of child care: she is the mother of four children, ages 11 to 22. She received her bachelor's degree from Vassar College, her master's and doctoral degrees from Harvard, and was the first female psychology professor at Yale. She now holds one of the University of Virginia's most prestigious chairs. She is the author of "Mother Care/Other Care," which has just been awarded the National Psychology Award for Excellence in the Media by the American Psychological Association.

"The book examines our assumptions about the nature of children and tries to deal with how we can meet children's needs and women's needs and the major changes in families and the way they can cope with modern life," she says.

"We know, for example, that very young children -- babies and toddlers up to the age of three or so -- really need a lot of loving contact with a few adults. They need to have trusting relationships. This does not mean, however, that it has to be the mother. It does mean you can't have babies switching from care givers every two weeks or toddlers switching to an army of impersonal care givers. We know that's not good."

Children, she says, "do well when they develop a relationship with someone who is a consistent person for them." There has been, she says, "a lot of research to the effect that day care is not a threat to the mental health of young children, but what really matters is the quality of that [care] which has to do with the kind of relationship that exists between the adults and the children and the kinds of activities and schedule and caretaking that goes on.

"Babies and toddlers need a lot of adult contact. Adults give them words and names for things. Adults interpret experiences for them. Babies need adults to give meaning to the world, whereas older preschool children also benefit from having other children around. They are learning about the social world of their peers. This is why nursery schools do so well, whereas people under three don't get a lot out of being around other children, and it can be a detriment to them.

"Parents are very sensible," she says. "Ninety percent of babies and toddlers are in family day care," where one adult, usually a mother, cares for them.

Children, she emphasizes, are not all alike. Some are shy, some are bold, some need long naps, some don't need any nap. Parents ought to find day care that fits their child, she says, and care givers whose philosophy of child rearing matches the parents'. Parents should also examine their own feelings about how attached to the caretaker they want their child to be.

And, she says, since more day care is available now, parents can be "pickier." They should make sure that parents can come and go from the care site any time of day, that other children there are happy, busy, and well supervised, and that the facility is run safely.

"One of the issues almost never discussed is how bad many families are for children and how some children would be better off with care givers who are benign and pleasant," says Scarr. "There are a lot of mothers who are not able to be comfortable and happy staying home and they get depressed. Depressed mothers are really bad for children because they don't interact with them. They tend to shunt them off and the child has a terrible day every day.

"We have not talked in this society very much about the fact that the most depressed group in this country are young mothers with children at home. Some 25 percent of those mothers are not very happy. Depression runs about 10 percent in the general population. We shouldn't make assumptions about the benefits of homes unless we know what the quality of the environment is. In many cases, the children are better off in day care."

That, she says, is a hard message to give to parents, but an important one. Equally important are Scarr's conclusions about day care: "If you know what to look for and you know what your children need, then there's no reason for you to feel guilty about being a career person as well as a mother. You can find appropriate care for your child and your child will be just fine."