As part of a study on mathematical problem solving of secondary 2 (13- to 14-years old) students in Singapore, 56 Secondary two students from ten secondary schools participated in this study. The purpose of this paper is to explore difficulties faced by 56 Secondary 2 students when solving problems. These interviews were analysed using the structure derived from Newman (1983) and Ransley (1979). From the interviews the difficulties experienced by Secondary 2 students who were prevented from obtaining a correct solution were: (a) lack of comprehension of the problem posed, (b) lack of strategy knowledge, (c) inability to translate the problem into mathematical form, and (d) inability to use the correct mathematics. (Contains 3 figures.)