The accumulation/distribution line or accumulation/distribution index in the stock market, is a technical analysis indicator intended to relate price and volume, which supposedly acts as a leading indicator of price movements.

The accumulation/distribution indicator (A/D) is a cumulative indicator that uses volume and price to assess whether a stock is being accumulated or distributed. The A/D measure seeks to identify divergences between the stock price and the volume flow. This provides insight into how strong a trend is.