Preface of the 15th International Workshop on Models@run.time’21

After a break in 2020, this year the 15th edition of the workshop Models@run.time is held at the 24th International Conference on Model Driven Engineering Languages and Systems. The workshop takes place virtually due to the Covid-19 pandemic on the 11th of October 2021. The workshop is organized by Sebastian Götz, Antonio Bucchiarone and Nelly Bencomo. Here, we present some highlights of the workshop.