This thesis is a collection of three essays that analyze procurement auction field data from different perspectives. In the first essay, the main policy question is whether the auctioneer should spend resources to induce more competition. In the second essay, I ask how the auctioneer can increase its revenue by changing contract characteristics like contract sizes and lengths. In the third essay, I develop and apply a test to detect collusion in auctions. The organization of this introductory Chapter is as follows. Sec- tion 1 gives an overview to the relevant literature on auction theory and the empirical analysis of auctions. Section 2 then summarizes the three essays, presents their results and discusses their contributions to the literature. Section 3 is devoted to drawing conclusions on the entire thesis. The three essays then follow in Chapters 2, 3 and 4.