So meet the latest members of the presidential portrait-painter’s pantheon: Robert Anderson of Darien, Conn., whose portrait of President George W. Bush was permanently installed at the National Portrait Gallery 18 months ago, and John Howard Sanden, who is putting the finishing touches on his portrait of the former president for the White House.

Anderson’s portrait is pointedly informal, with Bush sitting on the edge of a sofa in an open-collared western shirt, offering a wry smile to the viewer. We are not at the White House but at Camp David, the presidential retreat in Maryland. The room is comfortable and even a bit cramped, with simple furnishings. The one touch of opulence is a brown ceramic vase filled with irises on a table.

As for Sanden, his as-yet-unveiled portrait of the former president depicts him standing in a room in the White House, "almost smiling -- it’s more like a reassuring look," the artist said. Sanden noted that painting President Bush’s mouth was a little tricky, saying "the smirk shows up when he doesn’t want it, and he tends to mug for the camera, as though he can’t help it."

Rendering the setting also presented difficulties. For reasons that Sanden doesn’t understand, he wasn’t permitted into the White House to take photographs or make sketches; instead he was sent to look at photographs of the room in the National Archives in Washington, D.C. In any case, photographs of the finished painting have been sent to President Bush for his approval, and to the director of the White House Historical Association, "who didn’t exactly approve it, but he didn’t point out any errors, which is I guess the same thing."

A well-established portrait artist, Sanden "had done governors, cabinet officers, captains of industry, but I had never done a portrait of a president." At age 74, Sanden said, he had "pretty much written that one off." Then, earlier this year, he got the call -- actually, it was an email -- and has been hard at work on his portrait ever since.

Sanden hadn’t expected this assignment, because he hadn’t applied for it -- artists regularly submit portfolios to the White House curator -- or even sought it out informally via social connections (which play a large part in such jobs). Rather, the recommendation was made unasked by Annette Simmons, who with her husband Harold had invited to Bushes to dinner at their home in Dallas last February.

"We knew the Bushes from before they went to Austin," she said, referring to Bush taking office as governor of Texas in 1995. The recent dinner was celebrating the Bushes’ reemergence as private citizens and residents of Dallas, as well as Harold Simmons’ successful kidney transplant operation. The conversation turned to nearby Southern Methodist University, where the Simmons had donated $20 million for a new school of education and where Bush was setting up a presidential library.

Annette mentioned that Sanden was painting her portrait for the new school, which is named after her, and the subject pricked the interest of the Bushes. "It sounded like they were thinking about it for the first time," she said, although the former first couple may have simply been canvassing for recommendations.

President Bush asked her about Sanden. "Is he easy to work with?" She offered profuse praise, noting that he had done a portrait of their mutual friend, Dallas banker and SMU trustee Gerald J. Ford (no relation to President Ford), which she had liked a lot.

The day after the dinner party, Annette Simmons sent over to the Bushes three books of portraits by Sanden (including the most recent, Face to Face with Greatness), which the artist had given her. Within a few weeks, a staffer in the Bush presidential library emailed Sanden about coming in for a meeting.

When Sanden visited President Bush for the first time, in March, the former president met him at the door wearing a bathrobe. "He told me, ‘I didn’t know what to wear’," so the two men walked down the hall to look through his closet. Sanden made the decision about the suit, selecting "a middle-value gray suit, which was my preference, because a navy blue suit is not much fun to paint." Bush chose the tie.

"Don’t make my painting bigger than my father’s," Bush told Sanden. The caution wasn’t really necessary, since as Sanden already knew, from FDR on, almost every White House presidential portrait measures 50 x 40 inches. As it happens, all the presidents’ heads are about the same size, too -- about ten inches from chin to crown.

With presidential portraits, there’s a certain amount of repeat business. After looking at the White House portraits over the years, a president is liable to decide he wants one by the same artist.  James Anthony Wills, for instance, did portraits of Harry Truman, Dwight Eisenhower and Richard Nixon; Herbert Abrams did Jimmy Carter and George H.W. Bush; Everett Raymond Kinstler did Gerald Ford and Ronald Reagan.

Anderson, whose portrait of George W. Bush is now in the National Portrait Gallery, is also a member of this group. Back in 2003, he had painted Bush’s portrait for the Yale Club in New York City.

Anderson was acquainted with the president back when they were both at Yale -- they were in the same advanced Spanish class, struggling through Don Quixote -- and would occasionally run into him while Bush was attending Harvard Business School and Anderson was at the School of the Boston Museum of Fine Arts.

"We weren’t close friends, but we passed each other now and then. The amazing thing about George Bush is that, when you had a conversation with him, the next time you saw him, he would remember what you had said and ask you about it." However, after the early 1970s, their paths did not cross, and they lost touch for the better part of 30 years.

Still, Anderson had a hunch that President Bush would still remember him, and shortly after Bush took office in 2001 the artist contacted the Yale Club about doing a portrait of the president, submitting a portfolio. "I knew that the Yale Club had a tradition of commissioning portraits of alumni who became president and, as a Yale graduate and a classmate of the president and a member of the Yale Club, I thought I had a chance of getting the commission."

A year and a half later, Anderson got a call from President Bush, who first apologized for the connection, because he was phoning from Air Force One. Anderson admits to having difficulty rendering his subject’s mouth in both works. "I bet I painted the Yale Club mouth 100 times," he said, adding that he had an equal number of tries for the National Portrait Gallery painting.

"I was aware of the public consciousness of his smirking. I’d paint the mouth, wipe it off, paint it again, let it set for a couple of days, then decide, no that isn’t right either, so scrape it off and try again." At the unveiling at the National Portrait Gallery, Anderson confided to President Bush that he had had trouble with his mouth -- "he said, ‘That makes two of us’."

Few people enter their art careers as portrait painters; that decision tends to evolve from other things, and so it did with both Sanden and Anderson. Sanden received a Bachelor of Fine Arts in 1956 from what was then called the Minneapolis School of Art. "I didn’t learn a thing, although the drawing classes weren’t so bad." He worked doing layout and design, as well as illustrations, for the magazine and other circulars published by the Reverend Billy Graham from 1961 to 1969, taking on a number of side jobs for Reader’s Digest from 1964 to 1970, painting portraits of individuals profiled in that magazine. In addition, Sanden produced paintings -- many of which were of historical subjects, often of colonial America -- specifically for the publisher, Lila Wallace, which she used for Christmas cards and to decorate her home.

In the late ‘60s, Sanden moved to New York City, planning to seek work as an illustrator. In the evenings he took a portrait class at the Art Students League. Within a few months, he had compiled a portfolio of portraits, "and I took them over to Portraits, Inc." -- the preeminent gallery devoted to portrait commissions, based in New York City -- "and I got my first job that very day."

That first commission was from then-senator Peter Dominick of Colorado, who had been in the gallery when Sanden brought in his samples, and wanted a portrait of himself for a birthday gift to his wife. For almost 40 years Sanden has been steadily employed as a portraitist, taking time out only to teach portrait workshops, make portrait instructional videos or write books about portrait painting.

As for Anderson, he has been doing portraits professionally since 1973. At Yale, he was an American Studies major and planned on teaching high school, although he periodically submitted caricatures to the Yale Record, the university’s humor magazine. After college and a stint in the Navy, he enrolled at the School of the Boston Museum of Fine Arts, where he took his first steps toward a portraiture career, getting a job creating pastel images of Breck Girls for advertisements for the shampoo maker.

Anderson would work for Breck off and on into the 1980s, getting some flak from the women’s movement, particularly in 1987 when he led a nationwide search for the ideal Breck girl -- "the personification of American beauty," as he stated at the time. Through trade associations to which the shampoo maker belonged, he took on portraits of association executives’ wives. "Most of my commissions have come from word-of-mouth," he said.

Over the years, the artist has painted a number of notable figures from the world of academia and politics, including former Massachusetts governors William Weld and Edward King, former Massachusetts Senator Edward W. Brooke and former Yale chaplain William Sloane Coffin. Portraiture isn’t flattery, but Anderson noted that he did trim down Weld and Coffin by 20 or so pounds for their paintings. "You don’t want to do too much of that," he said. "You want to be true to life, and you might insult someone who says, ‘That was my favorite wart you left out’."

What is the fee for an official White House or National Portrait Gallery portrait? Reportedly in the $35,000-45,000 range, with the money being raised privately rather than allocated by Congress. The White House Historical Association finances the official White House portrait through the sale of White House guidebooks, Christmas ornaments and other souvenirs.

DANIEL GRANT is the author of The Business of Being an Artist (Allworth Press) and several other books.