This document discusses clustering techniques that can be used for analyzing sales data. It begins by introducing the importance of clustering large sales databases to extract useful knowledge that can help senior management with decision making. It then provides an overview of different clustering algorithms like hierarchical, partitioning, grid-based, and density-based clustering. The document also discusses the goals of clustering sales data, which include predicting customer purchasing behavior and improving knowledge discovery. It outlines the typical stages of sales data clustering as feature selection, validation of results, and interpretation of results. Finally, it reviews several papers that have used clustering and other techniques like association rule mining to analyze retail sales data.