Like many a musician, for Irish flute player and vocalist Shannon Heaton and her husband Matt, playing music has never been just about music. The couple, an integral part of Boston’s Celtic music scene for more than 25 years, find that playing tunes and songs – whether in performance or casual settings, stateside, in Ireland or Shannon’s childhood haunt of Thailand – often helps cultivate friendships. Sometimes, these friendships result in formal collaborations, but even if not, the pleasure of shared experiences and perspectives is bountiful.

Where Shannon Heaton is concerned, music also can spark holistic revelations and lessons about life itself, which she often shares via her “Irish Music Stories” podcast or on social media.

These threads will come together on March 13 in Harvard Square’s Club Passim, when the Heatons collaborate on a performance with O’Jizo, a trio from Japan that plays traditional Irish music. Opening the show will be Celtic harpist Riko Matsuoka, a Japanese native now living in Boston.  (The two bands also will perform on March 14 at Peaks Island Concerts in Peaks Island, Me., and on March 15 at Artistree in South Pomfret, Vt.)

Some things to know about O’Jizo, whose band name is a syllabic mash-up of its members, Kozo Toyota (flute), Koji Nagao (guitar), and Hirofumi Nakamura (accordion): They aren’t newbies, having first formed as a duo of Toyota and Nagao in 2008. They’ve toured in the US three times already and have four albums out. And, perhaps most significantly, they are not outliers, but part of a flourishing Irish music scene in Japan. Consider that Japan’s Comhaltas Ceoltoírí Éireann branch is more than 30 years old, Féile Tokyo has been a qualifying event for the Fleadh Cheoil since 2016, and bands such as Lúnasa (which recorded a live album in Kyoto a few years ago) tour in Japan regularly.

“It’s very lively over there,” says Heaton, who has been to Japan twice in the past seven years – once on her own and once with Matt and son Nigel last year. “You will find lots of seasoned players who have taken on mentorship roles and plenty of outstanding sessions that are as enjoyable as any here in Boston or elsewhere in the US. So, it’s very exciting to have Kozo, Koji and Daishi come here and to be able to introduce them to our traditional music community.”

Heaton’s initial contact in Japan was more than a decade ago when her friend, Yuka Nakafuji, asked Heaton for permission to include one of her tunes on an album Nakafuji’s Irish music trio – whose members included Nagao – was recording. A few years later came a similar request, and then Nakafuji asked Heaton if she might write a tune for the trio, and join them on tour in Japan, which Heaton did in 2019. By then, Heaton had also connected with O’Jizo, setting the stage for the Heatons’ 2025 visit, and the idea for O’Jizo to come to the US.

“They're great players, really creative arrangers, wonderful performers, and they're very funny,” says Heaton. “I learned a lot of Japanese before my trip, and that enabled me to appreciate more of their stage banter, which is quite hilarious. Kozo speaks very good English, and the other guys are really working on theirs. They don't have the facility, obviously, that they do in Japanese, but I’m sure they will give commanding performances and be quite entertaining on stage.”

That Irish music is all the rage in Japan should not be a surprising revelation. The music has traveled the world, an outgrowth of the Irish Diaspora but in more recent decades through the entertainment industry’s global reach – think “Riverdance” but also the likes of “Braveheart,” which Nagao watched as a junior high student and was intrigued by its use of bagpipes — and, of course, the proliferation of social media.

Then again, it’s not just Irish/Celtic music that’s been going in global circles, as is evident right here in Greater Boston. Whatever their cultural or ethnic heritage, area residents have long performed in ensembles playing traditional Arabic music or Indonesian gamelan, for example, or sat in on Brazilian choro jam sessions. 

There’s a universal question confronting any musician: It’s one thing to be able to present the form of a music, but what about the content? Are you simply playing the notes that are there, or are you conveying the heart and soul of the music? And if the music you’re playing is not native to your country, will listeners focus more on the inherent novelty in the situation, rather than on the quality of your performance?

Heaton sees two dimensions to that question. As a native of a country with close, historic ties with Ireland, and as someone whose family includes Irish ancestry, she explains, her entry to the music is somewhat easier, geographically and socially. Nevertheless, learning to play Irish music is “still much like learning a second language: You hear it, you get excited about it, you take trips to Ireland to learn it – and you can also learn about in the US from the great practitioners living here.”

But, she adds, there is also a deeper, more complicated issue. “We humans are tribal and

there can be perhaps a not-so-nice curiosity about things like, what’s a Japanese person doing playing Irish music – or, for that matter, what's an American person doing playing Irish music? On the outside, there’s a lot of welcoming, but I think sometimes once you dig a little bit deeper, there can be some fears, perhaps – guarded, uncomfortable feelings that people can have when someone from what seems a totally different world comes into their inner circle.”

Imagine, Heaton says, if she were to become adept at playing the shakuhachi, the Japanese end-blown bamboo flute. “However good at it I may be, at the end of the day, I am not a fifth-generation shakuhachi player and never will be. It doesn't matter how fluently I can play the music, or speak the language, or even inhabit the culture. In most people’s eyes, I'm coming to the music from ‘the outside.’ But while there may be a dubious aspect to that view, there’s also a beautiful one: taking pride in music that comes of a nation, of a people, of a culture. I think all of that is on display, big time, and that it just comes out as a curiosity.”

Where the members of O’Jizo are concerned, and Matsuoka and other Japanese natives playing Irish and other Celtic music, Heaton hears a fluency, a “real understanding of traditional music forms.” Their influences tend to be the more modern takes on Irish tradition, like Lúnasa, but Heaton says the respect for, and love of, the music are very noticeable.

“I think everywhere you go, people who get pulled into this enjoy the sounds, the melodies, which sound familiar to us; the rhythms are very exciting, whether we understand the dances associated with them or not. And the built-in socializing that can happen is very appealing. I think that's what attracts people all over the world to Irish music: that you can play it in public settings, and the people in the circle are enjoying the music together, and then there are others who simply like sitting and listening. Most of all, there’s the craic [pronounced “crack”]: what happens between the tunes or songs, where the musicians are talking, asking questions about what was just played, and oh, did you ever hear so-and-so’s version of that tune? 

“Being together in this increasingly wired world is that much more appealing, whether it's over Irish music or something else, and whether it’s in Boston or Tokyo or anywhere.”

Another ongoing project of Heaton’s culminated in the release last fall of her album, “Perfect Maze,” which comprises original compositions that bring together traditional Irish flute and modern classical chamber music. Much of “Perfect Maze” was inspired by the sounds and flight behaviors of butterflies and bees – the album title is a reference to the cells used in beehives – and harmonic and orchestration ideas from the likes of Aaron Copland, Claude Debussy, and Astor Piazzolla. 

But there was another layer to this inspiration, she says: “Without bees, we have no plants, no food, no wooden flutes. I’m frustrated by short-sighted policies that harm pollinators, the planet, the people. My reaction has been to try and think on a longer timeline, like back to Aristotle when he watched bees work together and thought of governing systems that help all creatures survive and flourish.”

Heaton has always enjoyed writing as a way of processing what's going on around her, and pairing writing with music is a means to perhaps make some sense and order in an increasingly fraught world. She does so with the realization that there are limits to how much she can do to fix or address the situations that cause her concern, “other than vote and try to make sure that my family, friends, and neighbors  are safe – and even that is a little bit out of my control. 

I guess the idea of making something that is resonant and thoughtful, at least at the

end of the day, will help me sleep with maybe a little bit more ease, beauty and meaning. It’s a way of letting in news and developments on my terms so I don't become debilitated – so I can still be available and helpful for my community and my family. So, I guess the only person that I can have any effect on really is myself.”

For tickets and other information about the March 13 concert with Matt and Shannon Heaton, O’Jizo and Riko Matsuoka, go to passim.org/live-music/events/matt-shannon-heaton-with-ojizo