This book constitutes the proceedings of the 19th International Conference on Theory and Practice of Digital Libraries, TPDL 2015, held in Poznan, Poland, in September 2015. The 22 full papers and 14 poster and demo papers presented in this volume were carefully reviewed and selected from 61 submissions. They were organized in topical sections named: interoperability and information integration; multimedia information management and retrieval and digital curation; personal information management and personal digital libraries; exploring semantic web and linked data; user studies for and evaluation of digital library systems and applications; applications of digital libraries; digital humanities; and social-technical perspectives of digital information.