For a market to rally it needs new buyers coming in, institutional interests not selling under the guise of strength. The Williams Electronic Market Accumulation Index can highlight excellent trading opportunities. This indicator measures professional accumulation and distribution along the lines of On Balance Volume, but far superior as it is designed for the new electronic markets. Look for divergences between market prices and Professional Advance/Decline. A new high in price not supported by this indicator is bearish, a new low in price that does not occur in this index is bullish.