IN 2006, James Griffioen was a litigator at a national firm in San Francisco with an 18-month-old daughter and a problem. “Having to go back to the office and work 70 hours a week — or 90, if you want to make partner — that cracked something in me. Something broke,” he said. “It was all the drive and ambition I had as a lawyer. I looked at it over the next five years and thought, ‘There’s no way I’m even going to see my kid.’ ”

So he huddled with his wife, a public interest lawyer. They took a hard look at their relative career satisfaction, discussed their desire to have one parent stay home instead of relying on day care, and decided that it made sense for the family to flip the ’50s sitcom vision of the American family and have Mr. Griffioen, now 35, leave the work force and join the nation’s swelling ranks of at-home dads.

Six years later, he considers himself less a Mr. Mom than a new archetype of the father as provider. “I sort of take things upon myself,” said Mr. Griffioen, whose family has added a son and moved to Detroit. “I don’t go to the store to buy my kids toys. I make them toys. I do woodworking, leatherworking. I learned all sorts of manly skills that I never would have had time to learn if I were sitting in an office 28 stories above San Francisco.”

Until recently, stay-at-home fathers made up a tiny sliver of the American family spectrum. Few in number, and lacking voice, they tended to keep to themselves, trying to avoid the inevitable raised eyebrows.