Dark Pools is a practical text dealing with the increasingly important topic of dark pools, or non-displayed, off-exchange trading and liquidity. A growing amount of institutional trading occurs away from exchanges and expansion in this little understood sector of the market is set to continue. The book is organized in three parts: Market Structure, Micro Issues, and Environment of the Future. The first chapters consider the development and evolution of the equity trading marketplace over the past two decades, including the creation of dedicated dark pool platforms, and introduce the concept of market liquidity, the formation of displayed and non-displayed orders, and the operation and structure of key dark pools. Attention then turns to the architecture of a typical dark pool, and how orders are routed to capture dimensions of non-displayed liquidity. This is followed by an analysis of the pricing and economics of dark liquidity and common trading strategies employed by institutions - including dark algorithms, high frequency trading and the controversial mechanism of 'gaming.' The final chapters analyze the regulatory and control framework and consider how dark pools may evolve in a post-financial crisis world.