Some of these costs occur before the transaction takes place (the ex ante costs) and some are incurred only after the transaction (the ex post transaction costs). Among the former are the direct and indirect costs arising from the contract selection process, including those of generating the relevant information and of drafting, negotiating, and safeguarding the agreement. The ex ante costs also include those arising from "adverse selection ", the principle (from the literature on insurance ) wherein, for any given insurance program and specified premium,