This dissertation consists of two essays that study the effects of single-stock futures (SSFs) trading on financial markets during the 2008-2009 financial crisis. In September 2008, the Securities and Exchange Commission (SEC) issued an emergency order to temporarily ban short selling of nearly 1,000 financial stocks. The literature found that the ban deteriorated valuations and market quality for banned stocks in stock and options markets. My first essay uses this short selling ban as an empirical setting to test the effects of SSFs trading on price discovery and market quality of banned stocks. I find that the short selling ban revived the trading activities of the SSFs market: SSFs trading volume increased significantly for banned stocks...