Klaus Happaniemi has an impressive list of accomplishments. He has designed products for brands like Marimekko and Iittala, published a book, created illustrations for The Observer newspaper and created scenography for Finnish National Opera - to name a few. Since 2010, he also runs his own brand Klaus Haapaniemi & Co together with designer Mia Wallenius.
Klaus Haapaniemi is probably most famous for his illustrations. They are usually detailed and imaginative with references to mythology and Finnish folklore. Often the Finnish national poem Kalevala is also mentioned in connection with Klaus Haapaniemi's designs.