Like a collection of hieroglyphs, portraits of old-time communist heroes lined the walls in a hall where left-wing Egyptian activists met one recent day. Marx wore his beard; Lenin read Pravda. On one wall, a new red banner bore an up-to-date message that not long ago authorities would not have tolerated: "Down With Tyranny in Egypt."

The activists, several of whom had spent years in jail, got down to work on strategies designed to end the 23-year rule of President Hosni Mubarak.

"I think this statement is too soft," said one. "We need to get to the point, and that is Mubarak."

"No, we should stay away from mentioning personalities," countered another.

Operating out of dingy offices in Cairo's decayed downtown of art deco palaces, activists of all stripes -- left, right and Islamic -- are testing the limits of political activity as they prepare strategies in anticipation of major reform in Egypt. The capital has become an arena of political effervescence.

Mubarak's government tolerates officially registered opposition groups, but many unofficial organizations have begun operating since a cautious liberalization of laws on association in the late 1990s.

It is far from certain that Mubarak will initiate or tolerate major reforms, but that seems to have dampened no one's enthusiasm. "Why wait?" said Kamal Khalil, a leader of the banned Revolutionary Socialist Party. "It is time for us to show we are steadfast and ready for Mubarak's downfall."

Still, fear of a crackdown is often evident when opposition groups meet. At the left-wing gathering, for instance, delegates refused to have their pictures taken.

For now, Mubarak and his large security services maintain a tight hold on power. Many political analysts think that despite fragile health, the 76-year-old president will seek a fifth term next year, through an unopposed referendum. Barring that, he would designate his son Gamal to lead.

The United States has pressed Mubarak to undertake a transition to democracy. But he has said that foreigners ought to stay out of Arab politics and that easing up could bring parties to the surface that want to convert Egypt into an Islamic republic.

Parties seeking legal status need the approval of a government-sanctioned committee headed by Safwat Sharif, who is also secretary general of Mubarak's ruling National Democratic Party.

In the past 25 years, the committee has rejected 50 requests for the creation of new parties. At present, 17 have official recognition.

By all accounts, Egypt's most influential opposition group is the Muslim Brotherhood, the granddaddy of Middle Eastern Islamic political movements. It is banned from politics, but some of its loyalists are members of parliament, and others operate openly in Cairo and other cities.

A spectrum of other opposition forces resents the notion that Egypt's only choice lies between Mubarak and militant Islam. "The Islamic threat is used by the government as a boogeyman," said Abdul-Ala Maddi, director of the International Studies Center, a front for developing a new Islamic party called Wasat.

Leftist ideology reached its peak in the 1950s and '60s under the rule of Gamal Abdul Nasser and then declined in influence in the 1970s and thereafter. Recently, leftists have spearheaded a series of street demonstrations against U.S. policies in the Palestinian territories and Iraq -- both topics on which most Egyptians are critical of Washington.

Increasingly, the protests have focused on Mubarak. "We are not cattle that can be passed from one owner to another," said Khalil, whose party is banned. He wants to make Mubarak's possible downfall a main subject of future demonstrations.

Leftists have also been the focus of an increase in human rights monitoring. The government suspects that some human rights groups are covers for political activities.

In June, Health Ministry inspectors raided the offices of the Nadim Center for the Psychological Rehabilitation of Victims of Violence, an anti-torture watchdog organization. The center runs a clinic where victims come for checkups and to get medical and legal referrals. The inspectors suggested that the clinic had too few stethoscopes and too much leftist literature and threatened to close it down.

"There is no question we are not just a clinic," said Suzanne Fayyad, a Nadim Center official. "But we have to link up with lawyers and human rights monitors. The government just wants us to measure blood pressure."

The Hisham Mubarak Law Center, another organization that battles torture, has refused to register with the government on the grounds that registration would open the way for interference. Instead, the center operates as a private law firm, even though its activities are overtly political.

"We want to challenge the right of government to control civil society," said Ahmed Seif, head of the center. "If our focus is torture, how can we ask permission from the government that practices torture?" The law center frequently hosts political strategy meetings among leftists grouped under the 20th March Movement for Change, an offshoot of March 2003 protests against the Iraq war.

"At first, Palestine and Iraq were the center of the protests. Now there is a consensus that domestic issues must take center stage," Seif said.

Parties on the right -- in Egyptian terms, this includes support for decentralized power and a market economy -- are also militating for an end to Mubarak's rule but are more cautious about taking to the streets. Ayman Nour, head of the Tomorrow Party, has published a 600-page program of proposed reforms that include multiparty democracy, a reduction of presidential powers and the elimination of socialist references in the constitution. He doubts that Mubarak will soon give up any real power. "The reality is bitter," he said. "We don't expect anything but cosmetic changes. Still, we must prepare ourselves for the right moment."

Nour, who is a member of parliament, broke from an officially recognized right-of-center group, but the government has so far refused to register Tomorrow. No matter: One recent day, he held what was effectively a campaign rally in downtown Cairo. He was carried into the hall by dancing supporters as pop music blared from loudspeakers. Politics was not a topic that night -- Nour told the group he had made lengthy speeches on reform the week before and the crowd had tired quickly of it. Instead, Nour invited a leading pop singer to perform. "This night is for fun," he told the gathering of about 2,000 people.

Although the status of Tomorrow is in limbo, Nour is recruiting members. He has also opened a Web site to present the party platform and is trying to organize a Web radio station to get around a ban that prevents him from publishing.

Even a new Islamic party has budded in Cairo's political greenhouse, and it is trying to challenge the Muslim Brotherhood. Wasat, made up of former Brotherhood members, wants to "incorporate Islamists into Egypt's political scene," Maddi said.

Like the Tomorrow Party, Wasat has been denied official registration. Maddi said the government considers Wasat a front for the Muslim Brotherhood. "This official attitude is counterproductive. Look at the results: The so-called underground Muslim Brotherhood operates the most successfully. If you abide by the law, you are weak and denied your rights."

Maddi said Wasat also finds ways to get around its lack of official sanction. It holds meetings ostensibly about the campaign for official recognition. "Of course, that includes recruitment and talking about subjects important to the public," he said. "We take our effort to form a party very seriously."

Kamal Khalil of the banned Revolutionary Socialist Party leads a protest in Cairo. Increasingly, such protests have focused on Egypt's president.