As far as I could see, this is the way business should be.

Indeed Comme il Faut is the French phrase for "the way it should be," an utterance that is usually delivered in Paris with a shrug of the shoulders, the wave of a hand, and a tone of resignation and sophisticated irony. It happens that the phrase is also the title of a beloved Argentine tango by Eduardo Ariolas, whose father was a Frenchman.

Ms. Muñiz and Ms. Coltrinari are both ardent tango dancers, and a few years ago both were having trouble with their shoes. They couldn't get the proper comfort and support from the dance shoes they were buying, despite the fact that those shoes were coming from France and Italy, the very centers of shoe design, and at a very hefty price. "But not every shoe that is well made is appropriate to dancing," Ms. Muñiz says. "Many of the highest quality shoes, like Ferragamo, Mark Jacobs, Miu Miu, they're made for appearance, not for comfort. I thought that for tango it would be more appropriate to design for comfort first and then for appearance. My feet hurt. So basically I went into business in order to liberate myself."

Women who buy from Comme il Faut applaud the comfort that the shoes provide while they're dancing. But the shoes are also instantly recognizable to almost any tanguera anywhere in the world because of their daring design. "No, there was no tradition of design in my family," Ms. Muñiz says. "But I began thinking about what a shoe needed in order to succeed as a great tango shoe. Beauty is an absolute must! But first there was comfort, and one day I met an Italian here in Buenos Aires who had learned to do shoe patterns in Italy. He taught me."

The elegant design concept remains critical, though. Ms. Sirois-Lucha says, "What you do with your feet is the language of tango. Feet that speak with each other in the dance cause the dance to be beautiful. A pretty shoe that holds to the foot properly will give you a pretty foot, and if you have a pretty foot you'll use it as an expression of your dance."

Ms. Muñiz describes the process she developed for her first designs. "I experimented for one year designing lasts and heels that were comfortable for me. There were thirty or more attempts, and the issue was that the support had to be exact to the curve of the foot. Finally when I got the shape I wanted, I designed my first pair, and those are the shoes I wore to my own wedding."

This was the modest beginning of Comme il Faut. A striking aspect of that beginning is that it defied all business school models for starting a new venture. For one, no venture capital. No capital at all, really. No business plan. No surveys to determine how much of a market there was. No previous business experience. "I was the most important customer I had," Ms. Muñiz smiles. "I was designing shoes simply for myself."