This thesis consists of three essays.

The first essay, “A Theory of Bank Illiquidity and Default with Hidden Trades”, develops a theory of banking to explore how the availability of trading opportunities for both banks and individual investors affects the link between illiquidity and default in the financial system. The results show that default emerges only in the presence of systemic risk, and when an unpredicted crisis hits the economy. Moreover, in contrast to the previous literature, default is not an efficient outcome of the economy.

The second essay, “Financial Liberalization with Hidden Trades”, studies how the availability of unregulated market-based channels for the circulation of liquidity in the financial system affects the process of financial integration, and the efficiency of the corresponding equilibrium, in a two-country economy with comparative advantages. The results show that the only level of integration which the two countries are able to coordinate is the one where the two banking systems are autarkic, but international hidden trades are possible. Moreover, the resulting consumption allocation is constrained efficient.

The third essay, “Bank Liquidity, Stock Market Participation, and Economic Growth”, develops a dynamic growth model with fully microfounded banks and markets to explain the observed decreasing trend in the relative liquidity of many financial systems around the world. The main result characterizes the threshold after which the agents in the economy are rich enough to access the market, where the relative liquidity is lower, and shows that the relative liquidity of the whole financial system (banks and markets) drops because of the increasing market participation. Some evidence consistent with this theoretical prediction is provided: a one-unit increase in an index of securities market liberalization leads to a drop in the relative liquidity of between 13 and 22 per cent.