In this written testimony to the U.S. Senate's bipartisan AI Insights Forum, GovAI Economics of AI Lead Anton Korinek encourages lawmakers to engage in scenario planning to prepare the workforce for advances in AI. The testimony argues that although AI brings promise of increased productivity, the fate of the workforce remains uncertain — especially if we progress toward artificial general intelligence (AGI). The potential for rapid disruption requires robust preparations, which are best performed through scenario planning. The testimony lays out three tangible scenarios: a historical scenario, a baseline AGI scenario, and an aggressive AGI scenario. In more transformative scenarios, fundamental reforms would become necessary to assist displaced workers and adapt safety nets, tax codes, and income policies. However, any reforms must be designed flexibly so that they work across scenarios. The testimony presents two concrete recommendations to lawmakers for how to flesh out the workforce implications of the described scenarios and start building the capacity and administrative infrastructure to respond. It concludes that technology should aim to provide shared prosperity, even if it reduces the competitiveness of human labor. If managed thoughtfully, AI can uplift all of society.