3D Investing: The Return-Risk-Sustainability Trade-off Frontier

How adding sustainability as a third portfolio objective alongside return and risk reshapes the efficient frontier, walked through on the S&P 500.

• The classic two-dimensional efficient frontier becomes a surface once a carbon or transition objective is added.
• Each point on the surface trades expected return and tracking error against a sustainability score.
• Charts plot expected return, portfolio volatility and weighted carbon intensity for S&P 500 constituents.
• The cost of decarbonization is expressed as basis points of expected return per tonne of intensity removed.