RILEM International Conference on Sustainable Materials, Systems and Structures (SMSS 2019) is a conference organised by Faculty of Civil Engineering University of Zagreb as a supporting event of RILEM Spring Convention from in Rovinj, Croatia. Both are organised in the year Faculty of Civil Engineering in Zagreb is celebrating 100 years from its establishment, making 2019 a perfect year for hosting such an important international event. The scope of the conference was to gather scientists, practitioners, members of technical committees and users of technical recommendations, to jointly at the same place discuss and envision the future sustainable development of materials, systems and structures in a holistic, global way. SMSS 2019 conference has gathered participants from 50 countries, from Argentina to United States of America, who will exhibit a total of 290 papers. The conference was sponsored by 10 international industrial partners, supported by 6 international organisations of scientists and practitioners and organised under the patronage of 4 governmental bodies. A total of 450 contributions which arrived was reviewed by more than 150 prominent reviewers from different fields. Event was organised by 16 members of the local organising committee and 6 invited international members of organising committee. As part of the RILEM SMSS 2019 conference, segment DURABILITY, MONITORING AND REPAIR OF STRUCTURES has consisted of 107 scientific papers which cover durability aspects of construction material in a variety of structures and harsh environments, maintenance and management of civil infrastructure and sustainable repair, rehabilitation and retrofitting. Among the others, the topics addressed are characterization of innovative and traditional durable materials, diagnosis of structures including service life design, seismic safety assessment, fire resistance, repair and conservation of heritage structures, advanced materials for structural rehabilitation, strengthening methods and case studies. Editors wish to thank the authors for their efforts at producing and delivering papers of high standard. We are sure that this Proceedings will be a valued reference of research topics in this important field and that it will together with the other volumes from SMSS conference form a suitable base for discussion and suggestions for future development and research.