This book constitutes the proceedings of the 20th International Conference of the International Graphonomics Society, IGS 2021/2022. Originally planned to be celebrated in September 2021, due to the COVID-19 pandemic it was held in June 2022.The 36 full and 3 short papers presented at the conference were carefully reviewed and selected from 41 submissions and reviewed by a committee of 67 reviewers. Out of the 41 conferences, 26 papers were selected to be published in this proceedings. The program was comprised of 6 oral sessions on the following topics: historical documents, forensic handwriting examinations, handwriting learning and development, and motor control. One additional poster session included papers on all previous topics, and three special sessions included papers on neurodegenerative disorders.