The decision-making process can be biased by virtue of the role that mental shortcuts play in human decision making. Although many researchers have studied this fact in form of psychological behaviours and behavioural economics, limited research has explored the role of heuristics and biases in the selection and definition of infrastructure projects. Accordingly, this paper provides a baseline for further research, presented in a “codex model”. A survey has been conducted to address the extent of people's awareness of heuristics and biases. The results show that more than 80% of the participants are not familiar with the concept of decision-making heuristics and biases. This research is important because it highlights the fact that increasing the awareness of decision-making heuristics and biases may lead to improved project decisions.