What shapes labor immigration policies? This dissertation explores in particular the macroeconomic environment and the influence of firms as key determinants. It argues that monetary policy plays a pivotal role in shaping labor immigration policy through its influence on the economic and political behavior of firms. Specifically, the expansion of monetary policy results in lower borrowing costs, motivating profit-seeking firms to expand, invest, and increase their demand for labor, including immigrant workers. This, in turn, drives firms to lobby for labor immigration liberalization. Notably, multinational corporations (MNCs) are expected to wield a stronger influence on the policymaking process due to their superior lobbying capabilities compared to their domestic counterparts. To empirically test this theory, I construct a novel labor immigration dataset to track changes in labor immigration across 25 high-income democracies over 50 years. This dataset is analyzed alongside monetary policy indicators and other economic and institutional factors through regression models. Case studies of Canada and Japan were also employed to provide detailed insight into the underlying causal processes. The empirical evidence uncovered emphasizes the significant impact of MNCs' borrowing costs on labor immigration policy changes, highlighting their size and favorable borrowing conditions that enable effective lobbying. This research not only contributes to the burgeoning field of labor immigration but also enhances our understanding of firm behavior and the outsized role of MNCs in policymaking.