The conception phase is one of the most important phases of software projects. In this phase it is determined which software development company will perform a software project. To obtain a software project, companies can have several bidding strategies. This thesis investigates if and how game theory can be a helpful tool to evaluate bidding for software projects. This thesis can be divided into two different parts: a theoretical and a practical. The theoretical part investigates the applicable parts of game theory in this thesis, explains what software projects are, explains the difference between costing and bidding and provides results of a literature survey about bidding behaviour. The practical part introduces a study to investigate strategies and bidding behaviour of software engineers, explains the experimental design that found the study, provides the results of the performed study and a discussion of the results. This thesis concludes that game theory contains some concepts that make it possible to evaluate bidding for software projects.