This special issue focuses on a variety of political-economy questions on trade and investment and is guided by a shared understanding that trade and investment processes can no longer be studied in isolation from each other. Three articles provide new insights into the study of the design of preferential trade agreements and effects thereof, two of which focus on the politically salient issues of non-trade concerns. A third one investigates which export sectors win from improved market access opportunities, in order words, how gains from trade are distributed. Two articles study the World Trade Organization’s dispute settlement system. One contribution is unpacking the role of the most important and influential firms and investors in affecting US behavior in WTO disputes, a second contribution studies how leadership changes in democracies and autocracies have different effects on dispute behavior. Finally, the special issue includes a new study on how the shadow economies in developing states are affected by the integration into the world economy (trade and investment) and by policy programs of the International Monetary Fund.