Shakil Choudhury, a filmmaker and community educator, immigrated to Canada from Pakistan when he was 5 years old. He spent his adolescence crisscrossing Ontario with his family, following the fortunes of his father, a family doctor. It was not always easy. Once, when his father took over a practice from a retiring doctor, two-thirds of the patients left: They preferred doctors with more familiar names. Displays of racism — some subtle, some less so — were so commonplace that by the time Mr. Choudhury became an adult, studying for a master’s degree in environmental studies, he realized he had internalized it.

He returned to Pakistan for an extended visit, a research trip for a book project, but also, more important, to build his cultural and personal pride. In 2000, not long after he returned to Toronto, Mr. Choudhury published “the brown book,” a collection of stories about South Asian Muslims in Toronto and Lahore. He has since used the book as an educational tool in antiracism workshops in cities around the world.

Shakil Choudhury is one of more than 750,000 Canadian Muslims, a diverse mix of South Asians, Arabs and North Africans, who defy generalization. The majority of Canada’s Muslims live in the province of Ontario (with the greatest concentration in the Toronto area), though there are also communities in Calgary, Edmonton, Montréal and Vancouver.

Officially, the Canadian government is committed to multiculturalism, which it enshrined in Canada’s Charter of Rights and Freedoms in 1971.

Rather than fostering a cultural melting pot, Canada embraced cultural and ethnic pluralism. In theory, one’s linguistic or ethnic heritage would have no bearing on “Canadian-ness.”

The reality of the immigration experience for Mr. Choudhury and others, however, has been difficult. And after the terrorist attacks against the United States on 11 September 2001, Canadian Muslims came under increased, often hostile, scrutiny.

Some of the harassment has been official: In 2003, more than 20 young Muslims were arrested on terrorism charges, and when these charges collapsed they were deported for petty immigration violations. But mostly, it is the barbs and incivility from their fellow citizens that have drawn the most complaints. The negative attention prompted the Canadian Arab Federation to assert that Canadian Muslims were being subjected to “psychological internment.”

Mr. Choudhury is part of a new generation of Canadian Muslims who are trying to bring their country closer to its multicultural ideals. Others include Salima Bhimani, who chronicles the experiences of Muslim women, and Toronto Star columnist Haroon Siddiqui.

They challenge stereotypes with nuanced portraits of their own communities, while engaging non-Muslim Canadian society as equal partners. They are also asking their own communities to resist self-segregation. By striving toward multiculturalism, they are also transforming it.

Census documents from the late 19th century first record the presence of “Mohametans” in Canada. By the early 1900’s, unskilled Muslim workers had trickled into the country to work the railways and mines. In 1938, the first Canadian mosque was built in Edmonton. At the time, there were only about 700 Muslims in the country.

The first wave of Muslim professionals and entrepreneurs arrived in the 1960’s, after Canada removed restrictions on non-European immigrants. Ever since, the Muslim presence has grown rapidly. In 1990, there were fewer than 300,000 Muslims in Canada. Since then, the population has more than doubled.

While some have prospered, Canadian Muslims on average have fared worse than their non-Muslim compatriots. Today, official unemployment among Canadian Muslims is about 14 percent — twice the national average — but experts believe 25 percent is a more accurate estimate. Many Canadian Muslims live in poor ethnic areas in Canada’s larger cities, enclaves that seem more like testaments to self-segregation and disenfranchisement than a rich, multicultural mosaic.

“One of the things that I remember ever since I was a little girl was Islamophobia,” said Salima Bhimani, an Ismaili Muslim, who grew up in what she called the “Indian ghetto” of east Toronto’s Thorncliffe Park. The winding streets are lined with tall slabs of low-income housing. Headscarves are ubiquitous. At the local elementary school — the city’s largest with 1,700 students — the non-Muslim teachers have difficulty identifying the students wearing headscarves.

“The first time I heard things like, ‘You’re a terrorist,’ it was clear that being Muslim was not cool, and I couldn’t necessarily stand up and defend it,” Ms. Bhimani said.

After 9/11, the atmosphere intensified. “There was a … backlash,” Mr. Choudhury said. “There were attacks on the streets, firebombing, veiled women were spat on.” Such violence was not widespread, and it did not reach the same levels as in the United States. But just as Europeans have grown anxious about increasing Muslim populations, similar concerns have been raised in Canada.

An example of this anxiety appeared last autumn in Canada’s leading newsweekly, Maclean’s. In an essay titled “The Future Belongs to Islam,” Canadian pundit Mark Steyn gave voice to Canadian nativists, suggesting that the ultimate goal of many Muslims in Europe and North America was to live under Islamic law.

Haroon Siddiqui, the most visible Muslim presence in Canada’s media, has made it his mission to combat Islamophobia. Born in Hyderabad, India, he moved to Toronto in 1967 and joined The Toronto Star a decade later. He said he uses his twice-weekly column to speak foremost “as a Canadian” and has spent his entire career making “democratic arguments” for tolerance. In 1970, he was criticized by many for his opposition to the War Measures Act, a temporary suspension of civil liberties that targeted French-Canadian separatists.

While Mr. Siddiqui, a recipient of the prestigious Order of Canada, speaks to the nation from a lofty perch, like-minded Canadian Muslims work at the grassroots level.

Suzanne Muir, a Canadian of Scotch descent, embraced Islam when she was 17 years old. After 9/11, she was anxious about how she would be treated. One day, as Canadian troops were arriving in Afghanistan, she came home and saw a picture her son had drawn in his kindergarten class. It appeared to be a self-portrait, with the boy standing beside a mountain with a stick of dynamite in his hand.

“I looked at it, and I totally freaked out,” Mrs. Muir recalled. “ ‘Oh my God,’ I thought, ‘My son is drawing pictures of himself blowing things up, and he’s the only Muslim in the school. His teacher must think we’re running the Al Qaeda preschool at our house.’

“I asked him what it was,” Mrs. Muir continued. “He said he’d watched a program on TV Ontario about diamond mining and that he wanted to be a diamond miner to get me a necklace for my birthday.”

Mrs. Muir said she lived in double fear: of a terrorist attack on Canadian soil and the reprisals innocent Muslims would face.

To combat such anxiety, Mrs. Muir has become proactive. She is a diversity coordinator for the school board in the Municipality of Halton, near Toronto. She also writes children’s books, including “Elephant Army,” an account of Alexander the Great’s final battle from the perspective of his Indian foes.

Much of the friction between Canadian Muslims and non-Muslim compatriots comes from an ignorance of the diversity of Islamic life in the country.

Non-Muslim Torontonians go to the middle- class, commercial neighborhood of Little India (also called South Asian Bazaar) for Indian buffets and spices. They are more likely to avoid the decaying apartment complexes and strip malls near the intersection of Jane Street and Weston Road, where Muslim Somali immigrants struggle to make ends meet.

In the offices of the Somali Immigration Aid Organization, local residents discussed the minimum wage before the conversation turned to housing.

“What do you do when your landlord never does anything to fix the building?” asked one woman.

Someone suggested she should complain to the city.

“But the city is the landlord,” she said.For Ms. Bhimani, official multiculturalism has meant too much emphasis on food, dances and festivals, and not enough real education about the varieties of Islamic life in Canada. In the United States, she said, Muslims may perceive more discrimination, but they also are more assertive about their cultural identity. “In Canada, we need to have more sophisticated conversations.”

Ms. Bhimani speaks regularly at churches and synagogues to build interfaith bridges. The reception has been warm, she said. Mr. Choudhury also has organized community dialogues. He recalled being approached by a non-Muslim woman who was glad to meet him because she was nervous about her Muslim neighbors. She knew nothing about them, she said, and was eager to learn.

More discussion is needed among and within Muslim communities, too, Ms. Bhimani said. She devotes much of her time to issues concerning Muslim women and has published a book, “Majalis Al-Ilm — Sessions of Knowledge: Reclaiming and Representing the Lives of Muslim Women,” which chronicles the lives of nine Canadian Muslim women.

One lively forum for discussion is the neighborhood gatherings organized by the Muslim Canadian Congress, a grassroots organization founded in 2002.

At a recent meeting in a restaurant in downtown Toronto, a diverse group organized by the congress was discussing whether it was appropriate for Canadian Muslim women to wear the hijab (headscarf) on the job, a practice protected by law in Canada.

Some railed against more traditional imams for stifling Muslim communities, while others argued for more empathy. Participants were not only Muslim, but also Jewish and Hindu. The only requirement for attendance is a commitment to the separation of church and state.

Are such efforts making a difference?There are promising signs. With the initial paranoia following 9/11 subsiding, Canadian officials have taken pains to defend publicly the Muslim population in Canada even as they try to crackdown on militants. Last summer, after the arrest of 18 Muslims who were allegedly plotting terrorist attacks in southern Ontario, Prime Minister Stephen Harper, the country’s most conservative leader in recent memory, defended multiculturalism, calling Canada’s diversity its greatest strength. Recently, Prime Minister Harper and Prince Karim Aga Khan IV, spiritual leader of Ismaili Muslims, signed a funding agreement for the Global Center for Pluralism to be based in Ottawa.

Moreover, earlier legal missteps by law enforcement officials have helped change public opinion. Canadian engineer Maher Arar, an alleged member of Al Qaeda, was deported to Syria in 2002. The charges were later exposed as unfounded and Mr. Arar returned to Canada. Polls showed Canadians were moved and appalled by his ordeal.

Canadian Muslims, too, say that Canada’s unique multicultural policies offer a promise of a rich Islamic experience in the predominantly Christian country, especially in comparison with other Western countries.

Last summer, Mr. Choudhury traveled to the Netherlands to lead antiracism workshops with Dutch citizens and recent immigrants. There, he said, he got a better idea of Canada’s strengths. “There’s no comparison. In the Netherlands, you are Dutch or you are not Dutch. The polarization is very strong. Canada looks different … it puts into perspective the openness we have here.”

Most Canadian Muslims agree with Mr. Choudhury. According to a February Canadian Broadcast Company poll, 80 percent of Canadian Muslims are “broadly satisfied” with their lives in Canada. Still, 17 percent believe others are hostile toward Islam.

Perhaps, unwittingly, Mrs. Muir best captured the multicultural ideal when she explained her reasons for becoming a Muslim.

“There’s no one breathing down your neck, no one telling you to do it this way or that way. To me, Islam asks us to be thinking, feeling human beings.”

That is what Canadian multiculturalism asks as well.

Daniel Aldana Cohen is a Toronto-based writer and editor.