The nature and condition of the large-scale glass fibre reinforced polyester resin outdoor sculpture by Dutch artist Joep van Lieshout: Mobile Home for Kröller-Müller (1995) is challenging traditional conservation ethics. Chemists, physicists, art historians, conservators specialised in different fields, interns and students have extensively researched and evaluated its condition. The artist was interviewed about the idea, meaning, function, aesthetics and behaviour of the artwork. In order to find suitable products for securing the conservation of polyester outdoor sculptures, mockups were made to test conservation materials. The resulting knowledge was used to explore active and preventative conservation measures. This resulted in decisions that push the boundaries of conservation ethics and a realistic proposal for conservation in cooperation with the artist’s company Atelier van Lieshout.