(Published in Co-operation with the National Council of Teacher of Mathematics) According to NCTM's Principles and Standards for School Mathematics, "Technology is essential in teaching and learning of mathematics; it influences the mathematics that is taught and it enhances students' learning." How does research inform this clarion call for technology in mathematics teaching and learning? In response to the need to craft appropriate roles for technology in school mathematics new technological approaches have been applied to the teaching and learning of mathematics, and these approaches have been examined by researchers world-wide. The second volume has a dual focus: cases and perspectives. It features descriptive cases that provide accounts of the development of technology-intensive curriculum and tools. In these cases the writers describe and analyze various roles that research played in their development work and ways in which research, curriculum development, and tool development can inform each other. These thoughtful descriptions and analyses provide documentation of how this process can and does occur. The remaining chapters in the second volume address research related issues and perspectives on the use of technology in the teaching and learning of mathematics. The lessons learned from the research presented in these volumes are lessons about teaching and learning that can be applied more broadly than solely in technological settings.