On Friday, activists from across the country will gather in Roxbury for a grassroots conference aimed at solving the housing crisis that grips Boston and other cities, by encouraging new development.

On Saturday, activists from across Boston will gather in Roxbury for a grassroots conference aimed at making sure that the new development transforming Boston doesn’t price working-class residents out of the city.

The contrasting conferences — YIMBYtown, at Roxbury Community College, and the Homes for All People’s Assembly, at First Church of Roxbury — offer a striking example of the delicate politics of housing in Boston amid the city’s building boom. Both are organized by people who ostensibly want the same thing: Housing that more Bostonians can afford. They just come at it from different perspectives and, in many ways, offer different solutions.

YIMBYtown is the third annual gathering of YIMBY — that’s “Yes In My Backyard’’ — activists. Broadly speaking, they are pushing for more housing development as a way to lower prices — basic supply and demand — and cast themselves as a counterweight to those who oppose housing over worries about traffic, an increased burden on schools, and other issues.

Organizers expect about 250 people to attend from the Boston area as well as from the West Coast, Texas, Canada, and even London. Somerville Mayor Joe Curtatone, Boston housing chief Sheila Dillon and MassHousing executive director Chrystal Kornegay are all scheduled to speak, and panels will touch on such wonky topics as zoning reform, parking requirements, and organizing political coalitions in development-averse suburbs. Organizers say they hope it will be part pep rally, part strategy session, with participants trading ideas for what works in their cities, and offering tips on building a pro-housing movement at local and national levels.

“Housing has never been a sexy issue, politically,’’ said Beyazmin Jimenez, a Lawrence resident who helped organize the conference. “It’s not like jobs, or the economy or health care, in terms of people being engaged. We hope to get it there.’’

But some people say they feel left out of that conversation, and that the focus of many YIMBYs on new housing overlooks the fact that most Bostonians can’t afford what’s getting built.

Several such groups, including some that advocate for renters facing eviction, are holding a “People’s Assembly’’ Saturday at First Church in Roxbury, where they’ll map out what organizers say would be a more “equitable’’ approach to development in Boston. City officials have been invited to attend, though none are scheduled to speak. The point is for residents on the front lines to set the agenda, said Carolyn Chou, an activist with Dorchester Not For Sale, which is organizing residents around a city planning process in Glover’s Corner.

“There’s lots of folks talking about housing affordability. The people who are closest to the issue, the people being displaced, should be making the decisions,’’ Chou said. “They’re the experts on what needs to happen.’’

The People’s Assembly is not explicitly a response to YIMBYtown, organizers say, but it’s not an accident either that it’s happening on the same weekend, and just a few blocks away. There were some raised eyebrows among Roxbury housing activists earlier this year when YIMBYtown organizers said their conference would take place at Roxbury Community College — in a neighborhood where many renters worry development surging through Dudley and Egleston squares will price them out of their longtime homes. They point to data showing that less than 10 percent of housing built in Boston this decade is affordable to lower-income renters and ask how new market-rate buildings — where rents often top $2,000 a month for a studio apartment — help working class Bostonians.

“We keep being told the solution of ‘build, build, build’ will trickle down to affordable housing in the most-impacted communities. But we don’t have any proof of it,’’ said Darnell Johnson, Boston coordinator for Right to the City, a national housing advocacy group. “We have complete proof of the opposite, which is that our folks get displaced and cannot afford the rents. It’s hard to trust and support a movement that is not working for our communities.’’

YIMBY organizers — many of whom, in Boston, work in affordable housing — agree they need to reach out more to lower-income communities, and engage residents who may have a different solution to the same challenges. Indeed, several panels at YIMBYtown are devoted to building alliances and partnering with “antigentrification activists’’ in neighborhoods that are changing too rapidly for some residents’ comfort.

But they also need to be pragmatic, said Jesse Kanson-Benanav, founder of A Better Cambridge, one of the region’s most active YIMBY groups. YIMBYs should support affordable housing, but demanding too much of it from private developers, for instance, can kill a project. Activists, he said, have to strike the right balance.

“It can be a tough conversation,’’ Kanson-Benanav said.

And there are points where all agree.

While the loudest housing debates are often in Boston and Cambridge, both YIMBY and antigentrification activists acknowledge there’s a bigger fight to be waged in the many suburban towns that aren’t building housing of any kind. Several activists said they may need to team up on Beacon Hill as well, where bills to protect Boston renters from eviction and to ease suburban zoning changes stalled at the end of this year’s legislative session.

In the big picture, Jimenez said, the two conferences — and the movements they represent — are more complementary than competitive. The housing crisis facing Boston is so immense that it will need multiple solutions, she said. The more people who are engaged in solving it, the better, she said.

“The Boston grass-roots groups are our comrades, and after the conference we need to find common ground with them,’’ Jimenez said. “I guarantee you we can.’’

Tim Logan can be reached at tim.logan@globe.com. Follow him on Twitter at @bytimlogan.