The biannual EUROPT(R)ODE conference is one of the major conference series on optical sensors. Since 1992, the EUROPT(R)ODE conference has been a forum for scientists and engineers from academia, research institutes and industry from all over the world. The conference attracts around 300 participants and focuses on all aspects related to the research, development and applications of optical chemical sensors and biosensors. Back to Graz! After 24 years the XIII edition of the EUROPT(R)ODE conference is returning to the location where it was founded: Graz in Austria.