Anthony D. Weiner has demystified the details of the 906-page Affordable Care Act for an electronic medical records company.

He has counseled a biofuel firm about expansion into the emerging markets of Latin America and Africa.

And he has plunged into the world of start-ups with his own green energy business.

Over the past two years, it appeared as if Mr. Weiner, once the irrepressible fireball of New York City politics, had spent his days as a stay-at-home dad, licking his wounds and mourning his ambitions after the salacious images and messages that he sent to women prompted his resignation from Congress.

But it turns out that from the moment he left public view, the man who had relied on a government paycheck his entire adult life was consumed by a corporate career whose profits and progress came to him, by his own account, with remarkable ease.