The advent of the World Wide Web is affecting many aspects of education, with claims that its use can transform the way students learn and are taught. WebQuest, the name given to an inquiry-oriented activity in which most or all of the information used by learners is drawn from the Web, is being suggested as a means of enhancing learning. This paper investigates how WebQuests might be effective in developing the problem-posing skills of pre-service mathematics teachers. Fifty pre-service teachers from a College of Education took part in this research and, with data from both an achievement test in mathematics problem-posing and a mathematics problem-posing beliefs scale, the effectiveness of using WebQuests in learning problem-posing was measured. The results show significant differences between those pre-service teachers who experienced WebQuests and those who did not; illustrating that it is possible to change the beliefs of pre-service teachers toward the role of problem-posing in mathematics education. (Contains 5 tables.)