Thermodynamics is a fundamental foundation of all engineering disciplines. A vast majority of engineering undergraduate programmes contain one or more courses on thermodynamics, and many engineers use thermodynamics every day to analyse or design energy systems. However, there is extensive anecdotal evidence as well as a wide range of published literature indicating that students often struggle to understand thermodynamic principles. In an effort to understand students' attitudes and perception of thermodynamics, including their expectations, experience and frustrations, an investigation was conducted. Following a review of the literature on the teaching and learning of thermodynamics in engineering, a survey questionnaire was developed and administered to close to a 1000 students in 17 thermodynamics classes at 13 universities in 7 countries. Survey results were analysed using statistical methods. This paper presents the findings of this investigation.