The guest editors, Prof. Vladimir Katić, from the University of Novi Sad (UNS), Novi Sad, Serbia, and Assoc. Prof. Chusak Limsakul, from the Prince of Songkla University (PSU) form Hat Yai, Thailand, have been invited by the journal editor, Prof. Simeon Oka, to present an overview of the state-of-the-art papers from the PSU-UNS International Conferences on Engineering and Technology (PSU-UNS ICET). All selected papers presented in this Thermal Science Journal Supplement are result of very rich collaboration between two universities, which officially started in 2002 when the first Memorandum of Understanding (MOU) was signed. Among other things, this document has initiated organization of scientific conferences for the resentation of research results, exchange of experiences and networking in all important engineering fields. The first PSU-UNS ICET conference started in 2003. It addressed both fundamental and application issues of engineering and technology. All together, conference topics include 18 engineering fields, with special focus on renewable energy sources and environment. It was organized by the Faculty of Engineering of the PSU and by the Faculty of Technical Sciences of the UNS.