Address: 3-14-1 Shinjuku, Shinjuku-ku, Tokyo (Shinjukusanchome metro station)
Isetan has become Japan’s largest department store chain since its purchase of Mitsukoshi in 2007. The flagship store in Shinjuku does show its age a little when compared to rival Takashimaya’s renovation. The luxury brands Fendi, Chanel, Etro, Armani, YSL, Gucci, Goyard, Missoni are all there accompanied by the more affordable lines such as Marc by Marc Jacobs, Burberry Blue label, Agnes B., Zadig & Voltaire. They also have a good selection of Japanese designers including Comme des Garcons, Yohji Yamamoto, Issey Miyake, Undercover, Jill Stuart, Cabane de Zucca, and Hanae Mori. And as in most Japanese department stores there is a whole floor devoted to food and another to restaurants.
PS. See below the location map in English. Tokyo maps provided by Google and showed at the "Location Map" section are in Japanese.