The existence of probability misconceptions at all levels has been well documented. Furthermore, these misconceptions have been shown to be widespread and highly resistant to change. Previous research has shown considerable success in overcoming misconceptions in the short term by basing the knowledge reconstruction process on problems which draw out beliefs held by students which are in agreement with accepted theory and which are therefore expected to receive correct responses. Such problems are referred to as anchoring situations or anchors. Anchoring probability situations which are conceptually analogous to misconception-prone/target probability situations were generated and tested with secondary mathematics students. The testing showed that probability misconceptions were common but also that anchors for overcoming these misconceptions could be generated. Anchoring situations were effectively used in overcoming students' probability misconceptions in the short term. A follow-up study showed that short term effects were retained over a 6-month period, thereby establishing the long term effectiveness of the approach. (Contains 35 references and 2 tables of data. Appendixes present a sample interview protocol and definitions of interview ratings.) (Author/RS)