This chapter focuses on the unintended consequences of the post-crisis mandate that over-the-counter (OTC) derivatives be cleared through centralized clearinghouses in an effort to reduce counterparty and systemic risk. Although central clearing has been widely implemented, it has reproduced many of the same characteristics of financial markets that contributed to the 2008 crisis: concentrated risk, moral hazard, and a reliance on faulty risk models. What accounts for the recalcitrance of the OTC derivatives market to a regulatory change? The chapter argues that focusing on the technologies and practices used to govern derivatives markets helps explain the absence of more radical regulatory policy shifts in derivatives regulation. Although there has been a significant shift in who regulates OTC markets, much less has changed at the level of the specific practices that govern these markets, and the chapter examines the continued reliance on netting, collateralization, and risk modeling within clearinghouses.