Modern portfolio theory was brought to us by Henry Markowitz winner of the Nobel Prize in Economic, 1990 along with Merton Miller and Williams Sharp. Modern portfolio theory is the basis of sound academic investing today. The concept of dissimilar price movement to manage volitity was first communicated mathematically by Harry Markowitz back in the 1950s. He has been recognized for developing the math formulas that are use today to measure volatility against expected return. Modern portfolio theory is cornerstone for sound prudent investing today.