This set of papers was originally developed for a conference on Issues and Directions in Mathematics Problem Solving Research held at Indiana University in May 1981. The purpose is to contribute to the clear formulation of the key issues in mathematical problem-solving research by presenting the ideas of actively involved researchers. An introduction provides an overview of each paper. The papers focus on the psychology of mathematical problem solving (R. E. Mayer), knowledge organization (E. A. Silver), implications from information-processing psychology, (D. J. Briars) building bridges between psychological and mathematics education research (F. K. Lester, Jr.), measuring problem solving outcomes (G. A. Goldin), a model for elementary teacher training in problem solving (J. F. LeBlanc), applied problem solving (R. Lesh, and M. Akerstrom), a concept-learning perspective (R. J. Shumway), and a statement of issues (H. L. Schoen). (MNS)