This thesis consists of three essays in international economics focusing on empirical questions related to the transmission of macroeconomic policies. The first essay, The Bank Lending Channel: A Time-Varying Approach, asks if and how the bank lending channel of the monetary policy transmission has evolved over time. It finds that the sensitivity of banks' lending to balance sheet liquidity – the key bank-specific characteristic identified in the literature – declines over time. The sensitivity of non-interest income, a proxy for banks' non-core activities, to lending, however, increases over time. The second, Does Public Debt Crowd Out Corporate Investment? International Evidence, seeks to understand the channels through which crowding out of private investment by public debt might occur. It finds that higher levels of public debt reduce investment for industries that need more external financial resources and increases the sensitivity of investment to internally generated funds for firms that are, ex-ante, more likely to be credit constrained. The final essay, A New Wave of ECB's Unconventional Monetary Policies: Market Impact and Transmission Channels, attempts to better measure the announcement effects of unconventional monetary policies. It finds that announcements after ECB President Mario Draghi's Jackson Hole speech in August 2014 are distinct from the earlier announcements with a more prominent impact on inflation expectations and exchange rates and increasing significance for the portfolio rebalancing channel. The essays discuss policy implications of the findings.