This study identifies the kinds of problems teachers pose when they are asked to (a) generate problems from given information and (b) create new problems from ones given to them. To investigate teachers' problem posting, preservice and inservice teachers completed background questionnaires and four problem-posing instruments. Based on previous research, a classification scheme was developed and used to categorize the problem statements. The findings indicate that the teachers--both preservice and inservice--struggled when asked to generate their own problems from a given set of information. Teachers had more success when they posed related problems from problems given to them. Teachers posed a greater number of responses for problem generation than reformulation. However, the reformulation responses were more often considered mathematical problems (versus exercises or nonproblems) than the problem generation responses. Teacher background and experience factors also play a role in problem posing. Implications for future research directions are discussed.