This paper evaluates four types of greenhouse gas emission reduction policies—carbon taxes, cap and trade (C&T) programs, tradeable performance standards (TCES) and technology-neutral clean energy standards (CES)—with a focus on the design levers available to policymakers to shape their structure and impacts. These design elements include production metrics, pricing mechanisms, technological neutrality, uniform standards, scope of coverage, balancing emission and cost risks, and managing distributional impacts. The paper concludes that each of these four policy approaches could reasonably satisfy a comprehensive list of policy criteria and as such be environmentally effective, cost effective, equitable, robust and durable; and at the same time also be preferable to either command and control regulations or 100% renewable portfolio standards approaches to deep decarbonization. The paper ends by identifying several implications for policymakers.