The Week of Science and Technology of the CAS is the most extensive science festival in the Czech Republic. This year, it was held for the 15th time already and took place between November 1-15, 2015 in Prague, Brno, Ostrava and other places over the intire Czech Republic. In total, it included 250 lectures, 60 exhibitions, science cafés, workshops, seminars, projections of scientific films and 75 open-house days. The open-house days at the institutes of the Czech Academy of Sciences are intended for all visitors interested in finding out more on the latest trends in the realm of science, in the work of scientists, the research projects of the Czech Academy of Sciences and the latest scientific instruments. and Jana Olivová, Luděk Svoboda.