... a magisterial, delightfully written history offering up portraits of the academic scribblers and entrepreneurial practitioners who created the index-fund revolution. It also contains common-sense wisdom that will benefit all investors ... [Wigglesworth] turns an arcane and potentially dull tale into a rip-roaring yarn.

... spirited ... With well-researched accumulation of one story after another, Wigglesworth brings to life how all aspects of investing have been transformed by indexation. We read of the anxiety, obsessiveness and isolation of those on a mission to launch a new way of investing. And he goes on to capture how the scrappy revolutionaries have had to adapt as they became the new ruling class ... Like a Russian novel, there are dozens of characters, so Wigglesworth employs Homeric epithets to anchor characters in our mind ... Many of their tales are already well told. But Wigglesworth manages to bring life to even well raked-over events ... In some respects, Trillions is a history of a transformation that is by no means over. This is a hard thing to pull off, not least as index investing has become so mainstream. So the issues he confronts in later chapters are broad market issues and not yet settled. He is a little too harsh on how companies are seeking to address the conundrums of how index firms should cast their votes as shareholders and try to play a meaningful role in corporate governance, as the recent case of shareholder activism at Exxon illustrated ... There are other issues I wish this first-rate book would have touched on ... We are living through an investment revolution as technology continues to transform how we invest. For those interested in understanding this better, Trillions is a book they should read.

Wigglesworth invokes each contributor’s humanity as well as their genius. The tangled pathway leading to the establishment of the index fund tracks nuances and power plays that are most fully understood by industry insiders. In Trillions, the complexities are laid bare in comprehensible language with insight into the long-game contributions of so many individuals, whose parts comes to fruition only decades after the initial ideas are generated, shared, and continue their evolution. With the feel of a thriller, Trillions illuminates the index fund and its place in the world of financial investment. A natural selection for business school collections; public libraries can expect demand both from patrons within the finance industry and those seeking to better understand how that world works.