Ato's 2013 Spring/Summer collection was held at Roppongi Hills. Under the theme "BRIGHT," the brand presented sophisticated spring/summer styles using lightweight materials and colors.

The first look featured three sporty styles: a T-shirt, pants, sneakers, and a functional backpack. Styled in refreshing hues like light gray, beige, and mint green, the collection featured a wide range of lustrous, flowing materials, including acetate, rayon, and cupra. The pants, blousons, and jackets featured prominent drapes, creating a relaxed feel. Faux suede cardigans and cut-and-sew tops appeared in the middle of the collection, adding texture to the materials. Faded colors, like khaki, beige, and blue, added a subdued, distressed feel.

The second half of the collection featured their signature suiting. This season, the collection featured a compact length and shape. The straps, which prevent the jacket from unraveling, were longer, adding a touch of gentlemanly style. Designer Matsumoto Yo said, "This time, the image is one that suits California. It has an atmosphere like the photographs of Ryan McGinley. I wanted to propose a wardrobe that can be used in everyday life."