0. Acknowledgements I. Applications A. Economic Applications in GAMS 1. Traffic Model 2. Extensions and Spatial Equilibrium 3. GAMS Related Items B. Vonthunen Land-Use (?) C. Spatial Equilibrium of Dairy Markets (?) II. Environments A. High-Level Interfaces 1. AMPL 2. GAMS 3. MATLAB a. Linear - LCP, QP, PVI b. Nonlinear - MCP (automatic differentiation in matlab?) 4. NEOS a. Function formats and AD b. CONDOR usage for large models 5. Stand-alone libraries B. Low-Level Interfaces 1. Problem Structure a. MCP b. CNS and conversion routines c. Solution report 2. Preprocessing Structure 3. Control Structures a. Output b. Errors/Warnings c. Timing d. Interrupts e. Allocation 4. Example of Usage - Convex QP III.Software A. Preprocessing and Statistics 1. Presolve 2. Statistics and Quality of Solution 3. Postsolve B. PATH 1. Theory 2. Implementation a. Features and Options b. Output C. PCPATH 1. Theory 2. Implementation D. SEMI 1. Theory 2. Implementation E. Comparison (?) IV. Conclusion and Future Directions (?)