The Office for the use of mistakes and coincidences is a performative installation. We sit at a desk, people are passing by and we kindly ask, if they want to have a certificates for one of their mistakes or coincidences, happened to them. If someone agrees, he or she must name a mistake or coincidence to us. Then we create a piece of art which is a unique and personal certificate. By reading it out loud, we appreciate and honour it and everybody is part of this little performative moment. Our tools for creating such a certificate are: exciting dialogues, humor, instant creative writing and presence. We use typewriters, stamps, gold leaf, pens, paints and various other materials. We set up the office for the use of mistakes and coincidences for many different occasions and in various contexts. You can find it in public spaces and in very specific situations, such as leadership training or events, or in the context of school culture development.