In July 1977, Dieter Roth arrived in Cadaqués, where Richard Hamilton spent his summers. Upon arrival, he took a sketchbook and started to apply all kinds of materials such as pencil, ink, salami, cigarette butts and the remains of sea urchins. After, he passed the pages to Hamilton to see if he wanted to continue working on them, as they had done on other occasions. Hamilton commissioned from a carpenter 60 pieces of wood the size of the notebook pages, painted them white, stuck Roth’s creations on them and continued working. They were all human portraits. The two friends realised that some of the images showed a resemblance to their self-portraits, so they were assembled in 30 pairs. Thus INTERFACES was born. Soon after, Roth suggested that they photographed themselves trying to appear as in the paintings. The photographic sessions took place in London a few months later. Hamilton filtered the negatives to achieve a resemblance with the paintings, which were presented as triptychs that could be combined in different ways depending on whether the right or left panels were open or closed. The creative complicity between Roth and Hamilton made it impossible to distinguish between the two authors in a work that is fresh, ironical and deliberately playful.