There are many methods available for prioritising software requirements. Choosing the most suitable one can often be quite difficult. A number of factors need to be considered such as the project development methodology being used, the amount of time available, the amount of information known about requirements, the stage of the project and the degree of information about priority required. This paper examines the type of information available at different stages in a project and matches it to the properties of prioritisation methods. It then recommends the usage of specific prioritisation methods at certain stages of a project.