This book constitutes the proceedings of the 23rd International Conference on Text, Speech, and Dialogue, TSD 2020, held in Brno, Czech Republic, in September 2020.*The 54 full papers presented in this volume were carefully reviewed and selected from 110 submissions. They were organized in topical sections named text, speech, and dialogue. The book also contains 3 invited talks.* The conference was held virtually due to the COVID-19 pandemic.