The main asset classes are stocks, fixed income products, and cash, with the fixed income and cash providing the stability to a portfolio, and the stocks (which may be held in mutual funds rather than individually) providing the growth. Since asset classes do not generally move in tandem with one another, diversification among asset classes is a means toward achieving the appropriate risk-return balance for an investor. See the Allocation Profile section for proposed asset allocations by investor profile.

Industry allocation refers to the economic sectors represented in the equity (stock and mutual fund) portion of a portfolio, which I have consolidated into these six sectors:technology, financial, health care, industrial, retail/consumer, and energy/utilities. Allocation by industry sector is at least as important as which stocks you own. See the Sector Allocation section for proposed sector allocations for growth investors and breakdown by industry sectors for the S&P 500 Index.

Once you have decided how much of your portfolio will be dedicated to growth, the aggressiveness of that stock portion is determined by the allocation among the industry sectors. Over the long term technology has provided the most growth and the most risk, as it is dependent on a healthy economy to do well; financial companies and health care companies have provided the next most growth, with less risk than tech stocks. These three sectors are over-weighted in an aggressive portfolio.

Industrial companies, retail/consumer stocks, and the energy/utility sector would be emphasized in a more conservative strategy, as they are typically less volatile (therefore, less risky) than growth stocks; and they do not provide as much growth.

In any case each of these sectors should be represented in a well-diversified portfolio, since good periods in one sector may coincide with bad times for other sectors, providing some balance. For example, if financial stocks are suffering from a period of low interest rates and a draught in investment banking, oil stocks may be thriving, because a shortage in oil is driving oil prices higher.

Diversification reduces risk.