This chapter presents concepts and samples to enhance your proficiency in three ADO.NET topics. The chapter initially drills down on datasets in ways not covered previously in the book. In particular, the first section highlights the differences between a typed dataset and an untyped dataset while showing you techniques for creating and managing each of these two kinds of datasets. Next, the chapter describes how to manage parent-child relations dynamically between two DataTable objects. The presentation reinforces the chapter s earlier material on typed vs. untyped datasets by demonstrating how to handle parent-child relations in each kind of dataset. The chapter concludes with a prototype design for a very common database application ”browsing and manipulating data with a series of text boxes on a form. The presentation of this topic follows a case study summary that starts with the form design issues and then systematically leads you through the code underlying each step to implement the overall task.