WASHINGTON, D.C. -- There aren't many places in the U.S. that can count poetry societies run by Afghan cab drivers. Washington has two. And they don't like each other.

"An Evening with the Dervishes" prefers what it calls the serious, scholarly pursuit of poetry. The group views itself as a literary clique focusing on masters such as Abdul Qadir Bedil, a 17th century poet and Islamic mystic, or Sufi. Its gatherings feature top scholars and poets.

"An Evening of Sufism," notwithstanding its name, brings all forms of Afghan poetry to large audiences. It also treats attendees to free refreshments and pop-music performances.

On a Friday evening earlier this year, Maroof Popal checked in on "An Evening of Sufism," the group he helped found and later abandoned to establish the more highbrow Dervishes. Inside a drab, low-ceilinged hall, an Afghan woman dressed in a black pantsuit rose to the podium. She informed the audience of nearly 200 that she'd just finished her poem in the parking lot.

Mr. Popal, 52 years old, couldn't contain his disappointment. "Why read a poem if you haven't given it much thought?" he muttered, gently slapping his head with the palm of his hand.

As another woman finished her poem about the "new and tragic phenomenon of suicide bombings in our beloved country," the cab driver walked outside for a smoke.

"Nowadays, by the grace of God, there are so many poets and writers out there," he said, taking a drag. "The question is, Do you want to listen to vulgar poetry or listen to someone who can offer us the real thing?"

The ethnic and political tensions that racked Afghanistan in the 1990s have cooled off, despite the recent Taliban insurgency. But having given up battling over the merits of the Taliban and the Northern Alliance, exiled Afghans here have found a new outlet for factional debate: how to celebrate the ancient Afghan art of poetry reading.

Poetry has deep roots in Afghan culture; the art form began more than 1,000 years ago in the ancient cities of Central Asia. Today, the Afghan passion for poetry, much of it Sufi-inspired and in Persian, extends to everyday life: Afghans pepper their conversations with snippets of poetry and engage in "poetic duels" in which each side recites a line of verse that begins with the letter that ended the opposing side's line.

The two groups meet in the same Masonic lodge in Springfield, Va., on different Friday nights each month. Mostly they adhere to Afghan social norms, treating each other with civility and even deference. Occasionally, they drop by each other's gatherings. But at times, their rivalries have burst into the open.

Members of "An Evening of Sufism" accuse the Dervishes of tearing down their flyers from Afghan stores, and have dubbed them "hash-heads," which in Afghanistan is a term associated with the uneducated. Wali Popal, the group's current moderator -- who is not related to Maroof Popal -- dismisses "An Evening with the Dervishes" as an "imitation."

The Dervishes say an "Evening of Sufism" lobbied the Masonic Lodge to keep them out. They also accuse the group of spreading false rumors that they pay big money to attract top scholars. Both groups deny the others' charges.

One of the Dervishes, Yusuf Bakhtary, a former school teacher and now a cabdriver, says he wants to ban music entirely from his group -- it occasionally invites a sitar player -- if only to distinguish it from "An Evening of Sufism."

He quotes Bedil: "Hypnotized by the spell of popular acceptance, how long shall I keep on uttering vulgarity?"

The poetry debate goes back to the early 1980s, when Maroof Popal, who left Afghanistan in 1978, began driving a taxi at Washington D.C.'s National Airport. There, he met other Afghan cabbies once or twice a week to read the poems of Bedil in any available space: the back of a furniture store, the showroom of an Afghan-owned car dealership.

At the end of 12-hour shifts, dog-tired and sometimes hungry, they'd sit cross-legged in a circle. Over cups of tea and candies, they tackled some of the most technically difficult poems written by the great Sufi poets, occasionally pausing for philosophical reflection over individual words -- "fog," "mirror," "silence."

Every now and then, when they found themselves stumped, they'd call upon a poet and Bedil scholar, M. I. Negargar. Calls to the former Kabul University professor -- who had taught one of the cabbies and lives in England -- soon became an integral part of their readings. Chipping in 25 to 50 cents each, they'd buy a phone card and hunch over the speakerphone as the professor brought the poems to life.

As Afghanistan degenerated into civil war in the 1990s, ethnic tensions flared among the exiled Afghans. Hoping that poetry would unite the community, the cabbies joined other like-minded Afghans to underwrite monthly public readings.

"People were revolted by politics," says Hashim Rayiq, a local Afghan civil engineer who helped formalize the poetry sessions. "I said, 'Let's have at least one night without politics.'"

The group they formed in summer 2000 -- "An Evening of Sufism" -- was quickly a hit. Within months it was holding monthly gatherings attended by hundreds, first in a banquet hall and later in a church and eventually in the Masonic Lodge. As the Taliban fell in 2001, it thrived.

"No Afghan organization has lasted six years," Mr. Rayiq says proudly.

Unless you count a 2004 rupture, that is. Maroof Popal and others say "An Evening of Sufism" was infiltrated by Tajik nationalists who supported the Northern Alliance, as well as former Afghan Communists. The newcomers, they say, tried to exclude the works of Pashtuns -- Afghanistan's dominant ethnic group, from which the Taliban hailed -- from the proceedings.

Wali Popal, the moderator of "An Evening of Sufism," denies the charges.

Yet even before politics intruded, some of the cabbies, who were never comfortable with the proliferation of poets and the size of the new group, had been itching to return to the Bedil readings and scholarly debates. Along with Maroof Popal, they broke away and founded "An Evening with the Dervishes" in late 2004.

One December night, the Dervishes dedicated their session to Prof. Negargar, whom they flew in for the occasion. More than 300 people showed up, mostly men in suits or black leather jackets, cell phones and keys dangling from belts. The only music for the evening would be the classical sitar, played by the son of one of India's great musicians, the late Vilayat Khan.

A silence fell over the hall as the professor spoke for two and half hours on the "concept of the unity of God in world religions" with dozens of lines of classical poetry recited from memory.

Four months later, "An Evening of Sufism" hosted an evening about Sa'duddin Ansary, a little known, second-tier 18th century poet. Wali Popal arranged for several of the poet's descendants to attend. A crowd of 200 showed up, nearly one third of them women.

The poems of Ansary moved the audience, but the loudest applause was reserved for the young poets, including the editor of an Afghan cultural magazine who read her poem lamenting suicide bombings. The evening ended with pop tunes performed by an Afghan keyboard player wearing a black shirt with a stenciled-on white tie.

Prof. Negargar says the sparring between the two groups is a little juvenile. "It is like a third grader who has started reading history poking fun at a first grader because the first grader studies only reading and math," he says.