Since research on meiobenthos was last compiled in a textbook (2008/2009), the number of theoretical and applied studies has been growing rapidly. Supported by new methods and digital evaluation, meiobenthology has developed into a wide field, with more and more researchers studying cross-disciplinary aspects. New perspectives were summarized in a booklet (2019) to draw attention to promising research directions. The present book, written by leading experts, is a compilation of new thinking, data, methods and approaches in many relevant fields of recent meiobenthos research. The topics addressed range from bacteria and biofilms to globally changing processes, from polar regions to the deep-sea and from freshwater ecosystems to the ocean. So, this book is not simply another meiobenthos textbook - it is an attempt to identify new horizons in meiobenthos research, driven by the vision of advancing knowledge and understanding of benthic ecosystems.