This year the Somerville HONK! Festival has invited several new bands to join in the clamor planned for the event, from both local acts and musicians from around the world. The lineup includes Band Land Brass Band, a group of Cambridge high school students inspired by HONK! to start the band, moving beyond their school marching band to use music for creative expression.

Also joining in the fun will be Unidos do Swing, a Brazilian brass band that mixes traditional U.S. jazz with the Brazilian carnival tradition. Unidos creates a spectacle of music and dance that beckons the listener to participate. After performing at HONK! Rio, they were so inspired that they went back to their home city of São Paulo and started their own HONK! Festival in 2017.

And then there’s Unlawful Assembly, a Twin Cities radical marching band collective founded to support causes of social justice, liberation, and equity.

These newly formed HONK! bands will have the opportunity to play alongside and pick up pointers from many veteran HONK! participants, including Red Flame Hunters, the first – and perhaps still the only – youth-oriented Mardi Gras Indian tribe in New Orleans. Red Flame Hunters have been working on sewing their lavish and ornate costumes for this season all year. Many who started at a young age with the Red Flame Hunters are now young adults, and will be joining the group at HONK! as a brass band. The group will be offering workshops on how they create their magnificent costumes as part of Saturday afternoon activities on Elm Street in Davis Square.

This year's HONK! includes all the features that have compelled thousands of participants to return year after year — family friendly Lantern Parades through the neighborhoods of Somerville; continuous free performances by dozens of HONK! bands all day in Davis Square; a return of the successful interactive Elm Street Art Space; the venerable HONK! Parade down Massachusetts Avenue to "Reclaim the Streets for Horns, Bikes, and Feet,” followed by a full afternoon of HONK! performances at Oktoberfest in Harvard Square.

This year the HONK! bands total more than 28, featuring many of the usual suspects, who will be coming mostly from the United States and Canada.

The HONK! bands participating this year are: aNova Brazil (Somerville, Artesian Rumble Arkestra (Olympia, Wash.), Band Land Brass Band (Cambridge), The Brass Balagan (Burlington, Vt.), The Bread and Puppet Circus Band (Glover, Vt.), The Carnival Band (Vancouver, B.C.), Chaotic Insurrection Ensemble (Montréal, Que.), Detroit Party Marching Band (Detroit, Mich.), Dirty Water Brass Band (Boston), Emperor Norton's Stationary Marching Band (Somerville), Environmental Encroachment (Chicago, Ill.), Extraordinary Rendition Band (Providence, R.I.), Forward! Marching Band (Madison, Wisc.), Leftist Marching Band (Portsmouth, N.H.), Minor Mishap Marching Band (Austin, Tex.), Musicians Action Group (San Francisco Bay Area, Calif.), New Creations Brass Band (New Orleans, La.), The Party Band (Lowell), Plezi Rara (Brooklyn, N.Y.), Rara Bel Poze (Boston), Red Flame Hunters (New Orleans, La.), Rise Up! Action Band* (Seattle, Wash.), Rude Mechanical Orchestra (New York City, N.Y.), School of HONK (Somerville), Second Line Social Aid and Pleasure Society (Somerville), Unidos do Swing (São Paulo, Brazil), Unlawful Assembly (Twin Cities, Minn.), What Cheer? Brigade (Providence, R.I.).

The parade on HONK! Sunday, from Davis Square to Harvard Square, will include all HONK! participating bands and many activist community groups, including: 350 Massachusetts for a Better Future, Alliance of Cambridge Tenants, Boston Workers Circle, Cambridge Artist Coalition, Indivisible Somerville, Mass Creative, Maud Morgan Arts, Midwives for Peace and Justice, MIRA Coalition, Mothers Out Front. Interested community groups can contact parade@honkfest.org if they’d like to participate in the parade.

The annual Kickstarter fundraiser is now in full swing at www.honkfest.org/kickstarter, with a deadline of Oct. 3 at 8 p.m. to reach its goal of $15,000. Anyone interested in volunteering can email volunteer@honkfest.org or housing@honkfest.org.

Visit honkfest.org/help for more information on volunteer opportunities or for more information on tax-deductible donations.