NEW YORK - Jonathan Hoefler sounded unmistakably like someone who had just fallen in love. He could not keep himself from smiling, and his speech, already rapid, seemed to quicken.
"When I first saw it," he was saying, "I just thought it was perfect. I can't think of anything to improve on that."
Mr. Hoefler, the 37-year-old founder of Hoefler & Frere-Jones, a Manhattan type foundry, was talking about a sketch of a capital letter N. Its diagonal beam was extended out both ways, top left and bottom right, in a subtly curved flourish.
The N was part of an alphabet sketched by Andy Clymer, a young designer at the firm, and it looked a little like a masquerade ball for 26 capital letters that had arrived early, stayed late and gotten into the good liquor.
The firm had just taken on a commission for The Nature Conservancy: a decorative typeface it could use for various purposes - letterhead, fax cover sheets, its quarterly magazine for donors.
It was the beginning of a three-month development process, although years sometimes pass between inspiration for a font and the completed work.
What happens in between is a little bit art and a little bit mechanical engineering, a balance between creativity and practicality. Type designers sometimes say their best work should be invisible.
They are making letters without making words - devising a means of communication, in a way, without saying anything at all.
MR. HOEFLER and Tobias Frere-Jones, the firm's other namesake, were born six days apart in August 1970.
They were drawn early to the shapes of letters: Mr. Hoefler recalls noticing at a young age that the type in opening and closing credits of a TV show were different, and learning years later that one had been hand-lettered and the other typeset.
For Mr. Frere-Jones, it was flipping through issues of National Geographic and noticing that the letters that spelled out, say, "Mediterranean Sea" was "something that only appeared there, and nowhere else."
Mr. Frere-Jones joined Mr. Hoefler's firm, then called the Hoefler Type Foundry, in 1999. Mr. Hoefler is color blind, and Mr. Frere-Jones says he has "no sense of perspective."
"I'm baffled by people who can glance at a car driving down the street and immediately identify not only its maker but its year of manufacture," Mr. Frere-Jones said. "It's a car. It's a red car. That's all I can tell you."
Several years ago, The Nature Conservancy was using a sort of knockoff version of Requiem, an elegant, imperial-looking Hoefler & Frere-Jones face with serifs, or small feet that adorn some letters. Another firm had ginned it up a bit to make it more decorative.
The Conservancy called Mr. Hoefler to fix some technical problems the decorative tinkering had caused. For Mr. Hoefler, irresistibly drawn to the history of type, it was not so simple.
"He started faxing me snapshots or scans of 14th-, 15th-century stuff," said Christopher Johnson, a senior creative manager at the Conservancy. "He saw it as an opportunity to reassess the whole typeface."
AT THE MOMENT, the Hoefler & Frere-Jones foundry typefaces are, to overstate it only slightly, everywhere.
Sports Illustrated, Sotheby's, Barnes & Noble, Nike and Martha Stewart are all clients. Gotham, a Frere-Jones font modeled after New York City building signage, might be the typeface of the decade: You can find it in the Saturday Night Live logo, on Netflix envelopes, on cans of Coca-Cola and bottles of Crest Pro-Health mouthwash.
When the Nature Conservancy came calling, it was looking for "an independent look, something different from what's out there," Mr. Johnson said. "A sense of formality. A sense of grace, that sort of thing."
Mr. Hoefler faxed him samples of the work of Ludovico Vicentino degli Arrighi, a papal scribe and calligrapher during the Italian Renaissance.
Mr. Hoefler, Mr. Frere-Jones and Mr. Clymer went back to Arrighi's letterforms - they have been known to literally put samples of type under a microscope - for inspiration on their project for the Conservancy.
They decided to give The Nature Conservancy an ornate version of Requiem outfitted with decorative swooshes and ornamentations that evoke Arrighi.
People who design letters are all about means, not ends. No one visits a gallery to look at an italic, lowercase R.
"If somebody notices something about a text typeface, it's probably not a compliment to the face. It's probably something the matter with it," Mr. Carter said.
Even after they had solved their major problems, Mr. Hoefler and Mr. Frere-Jones were making subtle adjustments, nipping and tucking.
"The final step is to make sure it's all square," Mr. Hoefler said. "Make sure all the family relationships are consistent."
It's no accident that type designers speak of "families" of fonts. They treat the letters as children being raised, in need of nudging, correcting, encouraging, occasionally reining in.
The swash capital letters created for The Nature Conservancy will probably one day - after the Conservancy's license is up - be for sale to designers everywhere. For now, it's part of a set used exclusively by the Conservancy, and christened Oakleaf.
"It has a more organic feel," Mr. Johnson said. "The stems" - he was talking here about the decorative swashes - "a lot of the way the typeface flows, a lot of them felt like maybe branches for a tree.
"It feels like nature."