The “princess phase.” So inevitable is this period in the maturation of girls today that it should qualify as an official developmental stage, worthy of an entry in Leach or Brazelton: first crawling, then walking, then the urgent desire to wear something pink and spark­ly. Whether we smile indulgently or roll our eyes at the drifts of tulle and chiffon that begin accumulating in our daughters’ rooms around age 4, participation in these royal rituals has come to seem necessary, even natural.

Yet the princess phase, at least in its current hyper-feminine and highly commercial form, is anything but natural, or so Peggy Orenstein argues in “Cinderella Ate My Daughter.” As she tells the story, in 2000 a Disney executive named Andy Mooney went to check out a “Disney on Ice” show and found himself “surrounded by little girls in princess costumes. Princess costumes that were — horrors! — homemade. How had such a massive branding opportunity been overlooked? The very next day he called together his team and they began working on what would become known in-house as ‘Princess.’ ” Mooney’s revelation yielded a bonanza for the company. There are now more than 26,000 Disney Princess items on the market; in 2009, Princess products generated sales of $4 billion.

Disney didn’t have the tiara market to itself for long. Orenstein takes us on a tour of the princess industrial complex, its practices as coolly calculating as its products are soft and fluffy. She describes a toy fair, held at the Javits Center in New York, at which the merchandise for girls seems to come in only one color: pink jewelry boxes, pink vanity mirrors, pink telephones, pink hair dryers, pink fur stoles. “Is all this pink really necessary?” Orenstein finally asks a sales rep.

“Only if you want to make money,” he replies.

The toy fair is one of many field trips undertaken by Orenstein in her effort to stem the frothy pink tide of princess products threatening to engulf her young daughter. The author of “Schoolgirls: Young Women, Self Esteem, and the Confidence Gap,” among other books, Orenstein is flummoxed by the intensity of the marketing blitz aimed at girls barely old enough to read the label on their Bonne Bell Lip Smackers. “I had read stacks of books devoted to girls’ adolescence,” she writes, “but where was I to turn to under­stand the new culture of little girls, from toddler to ‘tween,’ to help decipher the potential impact — if any — of the images and ideas they were absorbing about who they should be, what they should buy, what made them girls?”