Designing a shirt that carries large, practical pockets and a relaxed silhouette, yet stays clean under a backpack, was no easy task.Here, founder Akira and pattern maker Hirotomo look back on the process that brought it to life.

Akira: In our Trail Shirt series, including the UL Shirt, we deliberately avoided adding pockets. Customers often asked for them, but at the time we prioritized lightness above all. Adding pockets would reduce the breathability and blur the concept we were pursuing, so we resisted the idea for years.

But time has passed since the UL Shirt’s release, and I began to feel it was time to offer something different. That’s when we decided to take on the challenge of making a pocketed version of the shirt.

Hirotomo: Yamatomichi products have always been defined by simplicity — lightweight materials and a clear concept. At first, the idea of adding pockets to a shirt seemed to go against that spirit. But over time, I found myself drawn to the practicality they offered. I also knew that Akira had been wrestling with this dilemma for years.

Small pockets would only serve as decoration, while adding flaps or zippers risked complicating the design. To find the right approach, Akira and I built prototype after prototype, trying different fabrics and pocket styles, often abandoning them along the way. Looking back, those abandoned attempts became essential groundwork for what eventually emerged.

Akira: From the outset of revisiting the UL Big Pocket Shirt, the decision was clear: two large chest pockets would be part of the design. What wasn’t clear was how long the journey would take. Four years passed between that decision and the product’s release came far longer than expected.

Hirotomo: As with many of our projects, this one certainty took time. To reach the point of “this is it” required patience and iteration.

Akira: The biggest challenge was ensuring the silhouette remained elegant. We wanted something with a new pattern altogether, and so began experimenting with big-silhouette concepts.

Hirotomo: Because of the large pocket size, balance was everything. A shirt designed in the usual way would never work. The pattern had to be reimagined from scratch, and at times the prototypes looked more like jackets than shirts. It was an endless cycle of trial and adjustment

Akira: When the samples were finally tested in the field, the practicality of the pockets was undeniable. Having maps, tickets, or small items at hand proved surprisingly useful — both on the trail and while traveling.

Hirotomo: Pocket placement became another puzzle. They needed to sit low enough to be accessible even with a sternum strap fastened, but not so low that they disrupted the design. Countless adjustments were made before it felt right.

Akira: What took the most time, however, was the silhouette. Early prototypes had a big, relaxed shape that looked fine on its own but collapsed under the weight of a backpack. That wasn’t acceptable. Yamatomichi makes gear for hiking, and a shirt should look as good with a pack on as without. That realization set us on a new path: how to preserve the wide look while keeping the lines sharp with a pack.

Hirotomo: It wasn’t about simply adding fabric. If it looked like someone had just gone up a size, the concept would be lost. The shirt’s very structure had to be reconsidered. The final solution gave the upper chest a light, airy feel for ventilation, while tapering toward the hem for a clean finish.

Akira: Throughout the process, we reminded each other of the goal: to create a shirt unlike anything that had existed before.

Hirotomo: It was an ambitious challenge, and the results reflect that. The silhouette that emerged was something entirely new. Sleeve lengths, measurements, and comfort were refined again and again, until the balance was right.

Akira: There were at least three moments when I believed the shirt was complete, only to return to the drawing board. By the time it truly felt finished, four years had slipped by.

Hirotomo: The result isn’t a “big silhouette shirt” in the usual sense, nor is it oversized by the numbers. But when worn, it carries a sense of volume, while still allowing a backpack to sit cleanly and look sharp. Achieving that balance was a moment of real satisfaction, proof that the long process had been worthwhile. And yet, even now, it feels like the journey may not be over.

Akira: (Nods in agreement) Perhaps it isn’t.