As capital increasingly flows into private assets, investors seek the same analytical tools that already support public market investing. Private companies remain private for longer, private credit continues to expand, and real assets attract sustained institutional interest. This evolution creates demand for benchmarks and measurement frameworks that allow private assets to be evaluated alongside public assets within a unified investment framework. In addition, index methodology and tools solve many investor pain points of private markets, by delivering more consistent reporting and consistency of definitions of asset classes.

The Index Industry Association observes the rise of private market indexes as a defining trend for 2026. Institutional investors expect tools such as benchmarking, factor analysis, performance evaluation, risk measurement, and custom index creation to extend across the full investment universe. Private market indexes respond to this demand by bringing established public market practices into private markets, enabling third parties such as asset and investment managers to develop financial products that support investor choice.

Authored by the IIA’s CEO Kirsten Wegner with input from and in consultation with the IIA member firms, this white paper explores how index-based frameworks are being extended into private markets, methodologies for this complex asset class, and the critical role of transparency, governance and independent oversight in building confidence in these emerging tools.