Institutional Investor included William Blair as one of the "Top Global Investment Managers" in its ranking of transaction costs.
According to Insititutional Investor's Dan Weil, "over the past ten years, broker-dealers and asset managers have developed sophisticated transaction cost analysis (TCA) systems for equities, and are now starting to build TCA for the fixed-income and foreign exchange markets too."
TCA is a method of determining the effectiveness of a company's portfolio transactions— essentially, if trades were arranged at best execution.
William Blair was ranked sixth out of the top 10 global investment managers based on transaction cost difference against full-day volume-weighted average price for the 12 months ended June 30, 2016.