A variety of agent programming languages have been proposed but only few comparative studies have been performed to evaluate the strengths and weaknesses of these languages. In order to gain a better understanding of features in and their use by programmers of these languages, we perform a study which compares the two languages GOAL and POSH. The study aims at advancing our knowledge of the benefits of using agentoriented languages and at contributing to the evolution of these languages. The main focus of the study is on the usability of both languages and the differences between novice and more advanced programmers that use either language. As POSH requires Java programming experience, we expected novice POSH programmers to perform better on the tasks than novice GOAL programmers whereas we hypothesized this difference would not be observed between more advanced programmers. However, results suggest that there is no significant difference. The study does suggest that general experien ce and tooling support can make a difference. Analysis of the tasks and the observations made about the use of the languages, moreover, suggests ways to improve the experimental design in such a way that differences in usability of the frameworks could be established.@en