Globalization generates benefits for nations around the world, but it also creates winners and losers within nations. As former WTO Director-General Pascal Lamy puts it: ‘Globalization works because it is painful, and it is painful because it works’.1 This is why international economic integration inevitably creates a collective action problem; opposition by losers may thwart policies that would benefit nations overall.

The conventional approach to trade liberalization has been to liberalize trade through international agreement and address subsequent domestic fallout and spillovers through domestic policies. In consequence, international obligations in trade liberalization are not legally connected with ‘flanking’ measures to address their negative effects. We discuss the shortcomings of this conventional approach with respect to labor adjustment and environmental protection: for political reasons, trade liberalization requires today the simultaneous regulation of labor and environmental spillovers. We suggest a novel approach to trade liberalization that includes the necessary flanking policies as part of, or linked to, the international agreement itself. This novel approach seeks to achieve the best of both worlds: reaping the benefits of international trade while making sure that negative spillovers are effectively addressed. To illustrate the intricacies of this approach, we introduce a new conceptual framework covering the negative effects of trade liberalization and flanking or mitigating policies, and a proposed novel approach in the form of trade liberalization packages and package treaties. Trade liberalization packages and package treaties are currently emerging around the world (e.g. sustainable palm oil in EFTA–Indonesia) and deserve our close attention.

In the past decades, a backlash against globalization has been brewing, especially in advanced economies. Despite this backlash being only partly determined by trade, we observe an increasing demand for transparency on procedures, methodologies, and results. Impact assessments (IAs) aim at identifying expected effects of trade agreements and at highlighting policymakers' concerns, thus representing an important tool to foster public acceptance. To help us identify spillovers of trade liberalization, we construct a country and sector-specific database of impact assessments. This database provides an overview of the evolution of the coverage and methodological approaches taken by the EU and US for their IAs. We rely on official EU and US sources over the period 1990–2023. We first observe differences in terms of methodology and institutional framework within and between the two regions. Secondly, the coverage of non-trade outcomes has evolved over time both for the EU and the US, with the inclusion of more labour, environmental, and human rights indicators as well as cross-cutting issues. We observe that the depth of the evaluation is correlated with the partner country's social protection and environmental performance. Lastly, we find that the inclusion of a sector in the analysis is driven by economic reasons in the EU but by political reasons in the US.

This article studies the incorporation of package treaties in domestic law and administrative practice, including the functions these treaties serve once in force. This sketch of the domestic operationalization offers a window into the institutional design choices that shape how lawmakers craft the regulatory ecosystem in which flanking policies are carried out. The typology for understanding how governments situate package treaties in their domestic regulatory spaces is introduced, arguing that the ‘package’ of legally binding trade liberalization commitments and mutually agreed flanking policies is shaped by both legislative and regulatory choices that are often underestimated and overlooked. DUS trade agreements are used as a case study, finding that the US government's treatment of each of its trade agreements tends to follow a common pattern: only a small part of the agreement is transposed into domestic law; complex and robust institutions are built around the agreement to embed it deeply into the trade policy work of the executive branch; and, the entrenchment of US trade agreements has a significant enabling effect across a wide range of cross-border regulatory engagements that US agencies think of as ‘monitoring’ or ‘enforcing’, among other labels. Finally, the policy choices against the goals laid out by proponents of package treaties are assessed.

Flanking policies – policies that aim to address potential negative effects of trade liberalization, and/or the concerns of domestic stakeholders regarding those negative effects, and that are either legally or factually linked to trade liberalization – have been a critical component of international trade policy since at least 1962. Over the years, however, flanking policies have changed. This Article argues that there is a heretofore unnoticed distinction between what I term first-generation flanking policies and second-generation flanking policies. Specifically, first-generation flanking policies target negative economic effects, or costs, of trade liberalization experienced within the enacting country. Trade adjustment assistance is the paradigmatic example. By contrast, second-generation flanking policies target non-economic costs that arise outside of the enacting country. Examples include the European Union's Carbon Border Adjustment Mechanism, Deforestation-free Products Regulation, and the United States' Uyghur Forced Labor Prevention Act. Because second-generation flanking policies directly target foreign activity, they often employ more trade-distorting policies – tariffs, imports bans, and associated administrative hurdles for imports – than first-generation flanking policies, which more often relied on domestic subsidies. Moreover, they reflect a significant reorientation of the limits of state authority in international trade law. Whereas authority to tax and regulate production in international economic law has historically been based primarily on a territorial link to productive activity, second-generation flanking policies target production but rely on a territorial nexus with consumption of goods and services.

This article examines the rationales for addressing sustainability and social inclusion in trade policy and the tradeoffs among imperfect institutional choices in doing so through ‘flanking policies’. It examines three types of negative spillovers or externalities implicated by trade: material, moral, and social/political. Section 1 defines terms and sets forth the argument. Section 2 typologizes the three categories of negative externalities and then highlights the challenges posed for flanking measures given the reciprocal nature of externalities. It respectively addresses environmental harms and labor and social inclusion concerns. Section 3 assesses different institutional alternatives for addressing negative externalities, dividing them between domestic measures targeted at protecting domestic concerns and international ones, such as package treaties. Section 4 shows how the concept of a flanking measure can be flipped, so that environmental sustainability and social inclusion become the core and trade measures become the flanking policies. Section 5 concludes.

The post-World War II liberal international order coupled trade liberalization with a range of flanking measures, both outward-looking and inward-looking. This system, coupling domestic-level compensation with international-level flexibility, no longer functions as effectively as it once did. To consider how a renewed set of flanking policies might address, or even prevent, a backlash against trade liberalization, we explore why the earlier system (embedded liberalism plus temporarily tolerated relief) did not always function effectively. We note the challenges associated with generous domestic compensation schemes, especially in the face of capital mobility and fiscal pressures. We discuss the interstate tensions generated by the use of temporary relief measures, such as escape clauses and safeguards, and we also discuss how the expansion in membership of the multilateral trade system (and particularly the inclusion of countries with a greater array of economic institutions and factor endowments) exacerbates these challenges. Finally, we consider how the domestic politics of flanking policies could differ from those used in an earlier era.