For a speculative investor, there are two aspects to optimizing a trading strategy. The first and most important goal of a trader is to achieve a positive expected risk-adjusted return. Once this has been achieved, the trader needs to know what percentage of his capital to risk on each trade. Within the trading fraternity this task is often know as money management. The underlying principals of money management apply to both gambling and trading, and were originally developed for the former. The problem of how to maximize growth of wealth has been solved: maximize the expected value of the logarithm of wealth after each period. However, most investors are unwilling to endure the volatility of wealth that such a strategy entails, and as John Maynard Keynes reminded us, in the long run, we're all dead. For this reason, a compromise between the optimal growth strategy and the security of holding cash is often recommended. This note reviews the literature on money management.