marked the collaboration between apparel and accessory brand Stussy and Hello Kitty. Stussy worked with Hello Kitty on a collection focusing on the Hello Kitty character with Stussy signature graphics. This collection included T-shirts, keychains, and hoodies. For a long while afterwards, Sanrio made no particular effort to replace Hello Kitty's designer. Soon Yuko Yamaguchi joined Sanrio in the midst of the Kitty boom in 1978, at the age of twenty-two, hoping to get a job focused on advertising. When Tsuji had learned of the team planning to abandon Kitty, he fought to keep her and decided to hold an in-house competition for new concepts for Hello Kitty. Hello Kitty ( ハローキティ, Harō Kiti) is the best-known of Sanrio's fictional characters, created in 1974. Hello Kitty is drawn simply with a trademark red bow. Registered in 1975, Hello Kitty is now a globally known trademark. Hello Kitty has been marketed in the United States from the beginning and has held the position of U.S. children's ambassador for UNICEF since 1983. The brand rose to greater prominence during the late 1990s when several celebrities such as Mariah Carey adopted Hello Kitty as a fashion statement. Like other Sanrio characters, Chococat appears on a variety of merchandise including stationery, coffee mugs, plush toys, bath towels, hats, purses, notebooks, etc. In America, Chococat is one of Sanrio's most popular characters with both adults and children. Hello Kitty cameos with Keroppi and Badtz-Maru in the first few minutes of the 2018 film Ready Player One. Kitty also gets a few more appearances in the film such as a motorcycle decal and as a costume.

While Sanrio is the main producer and distributor of Chococat goods, they do occasionally other companies a share in the fun. Some of them are:in the 2013 Character Ranking, if he reaches 30th place or higher, he will try to be popular in Japan as well. However he failed to reach that rank.

There is a themed restaurant named Hello Kitty Sweets in Taipei, Taiwan. The restaurant's decor and many of its dishes are designed after the Hello Kitty character. Keroppi ( はすの上 けろっぴ, Hasunoue Keroppi) (also known as Kerokerokeroppi) is a frog character with large eyes and a V-shaped mouth. Keroppi loves adventure, and his bubbly personality makes him popular around Donut Pond. He has a brother called Koroppi and a sister called Pikki. Most often he is seen with his little snail friend Den Den, always tagging along a little behind. Keroppi is a fantastic swimmer and singer (but not at the same time). For the 50th anniversary of Sanrio, Sanrio and Girl Skateboards collaborated and released skateboards with a Hello Kitty graphic. There is a Hello Kitty store in Africa opening 2013. As of August, 28th, 2014 it was rumored Hello Kitty is a human girl and not a cat. However, it has been confirmed that Hello Kitty is actually a gijinka (anthropomorphic) cat and not human. [1] The character's first appearance on an item was a vinyl coin purse in Japan, which ended up being the hottest selling item that year which came as a surprise to everyone.Sanrio and various corporate partners have released Hello Kitty-branded products, including the Hello Kitty Stratocaster electric guitar (since 2006, with Fender in the US) and even an Airbus A330-20 commercial passenger jet airliner, dubbed the Hello Kitty Jet (2005–2009, with EVA Airways in Taiwan). Hello Kitty is included as part of the Sanrio livery at the Japanese theme parks Harmonyland and Sanrio Puroland.