Active is More than Just an
Investment Approach

Being 100% active employee-owned promotes a dynamic environment in which our business and investment processes continuously evolve in pursuit of better client outcomes.

Watch video: Summit Research Platform


Collaboration and Perspective

William Blair’s proprietary Summit research platform enables our portfolio managers and analysts to dynamically and efficiently work together to identify high-conviction investment ideas in the pursuit of better client outcomes. Watch our Global Equity team members discuss how they leverage the tool.



We Evolve to
Better Serve You

Stability and Evolution

Building on the foundation of our firm’s stability, we are continuously evolving the business and our investment processes to meet your needs while remaining true to our core investment tenets.

Active Environment

We have created an environment in which investment professionals can thrive practicing the profession of investment management and are committed to seeking long-term success for our clients.

Uncompromising Integrity

We make investment decisions based exclusively on what’s best for you. We earn your trust through transparency and an unwavering commitment to active investing and meeting your investment needs.


We Have a Passion
for Investing

Unique Voices, Shared Values

Our autonomous investment teams have the freedom and flexibility to deliver high-conviction active management while benefiting from a culture that promotes a shared foundation of principles and values.

Curiosity and Conviction

A culture of deep curiosity and conviction promotes ongoing investment-process improvements while each team stays true to its investment philosophy.

Disciplined, Proven Process

Our consistent, rigorous, and repeatable process helps strategies to perform as clients expect.


We Build Long-Term

100% Active Employee-Owned

Our broad-based ownership structure seeks to align with our clients’ long-term interests—we have no outside influences or constantly changing short-term priorities.

Dynamic and Stable

Our dynamic ownership helps retain top talent, ensuring our best investment minds are working on your behalf.


Our broad-based, active ownership means we build client relationships that last year after year rather than quarter to quarter.

It is essential that our investment approach and related investment outcomes are as relevant in the future as they’ve been in the past.

Ken McAtamney, Partner
Portfolio Manager, Global Equity Team

High-Conviction Active Management:  Alpha Opportunities


Active share is a measure of the percentage of stock holdings in a manager’s portfolio that differs from the benchmark index. It is a key indicator of an investment manager’s:

  • Conviction in the team’s approach
  • Willingness to be different from the benchmark (not hug the benchmark)
  • Opportunity to outperform the benchmark


Source: William Blair. The data shown above is based on each strategy’s representative portfolio.



Our clients are at the center of everything we do.



We hold to the highest level of ethics in all of our business and community engagements.



Our everyday actions are informed by our perspective as global citizens.



The quality of our people is our greatest strength.



We cherish our independence and appreciate the objectivity it brings.



We apply focus and commitment to every challenge.



Creating value is our job; sustaining enduring value for our clients is our mission.



Opportunity to be Better Than Average

The key benefit of active management is the opportunity to be better than average by identifying and dynamically allocating capital toward companies that are outperforming over time. The challenge is to identify active managers that develop a culture and a repeatable investment process that may provide superior long-term investment returns.

Gain More Insights


Create an
Enduring Partnership

Our active ownership culture creates long-term client relationships by helping you achieve successful investment outcomes. Contact us to learn how we can partner with you.

Any statements or opinions expressed are those of the author as of the date of publication, are subject to change without notice as economic and market conditions dictate, and may not reflect the opinions of other investment teams within William Blair Investment Management, LLC.

This content is for informational and educational purposes only and not intended as investment advice or a recommendation to buy or sell any security. Investment advice and recommendations can be provided only after careful consideration of an investor’s objectives, guidelines, and restrictions.

Factual information has been taken from sources we believe to be reliable, but its accuracy, completeness or interpretation cannot be guaranteed. Forecasts, estimates, and certain information contained herein are based upon proprietary research and should not be interpreted as investment advice, as an offer or solicitation, nor as the purchase or sale of any financial instrument. Statements concerning financial market trends are based on current market conditions, which will fluctuate. William Blair does not provide legal or tax advice. Please consult your tax and/or legal counsel for specific tax questions and concerns.

Investing involves risks, including the possible loss of principal. Equity securities may decline in value due to both real and perceived general market, economic, and industry conditions. The securities of smaller companies may be more volatile and less liquid than securities of larger companies. Investing in foreign denominated and/or domiciled securities may involve heightened risk due to currency fluctuations, and economic and political risks, which may be enhanced in emerging markets. Investing in the bond market is subject to certain risks including market, interest rate, issuer, credit, and inflation risk. Currency transactions are affected by fluctuations in exchange rates; currency exchange rates may fluctuate significantly over short periods of time. Diversification does not ensure against loss. Any investment or strategy mentioned herein may not be suitable for every investor. Past performance is not indicative of future results.

The MSCI ACWI IMI Index is a free float-adjusted, market capitalization-weighted index that captures large, mid, and small cap representation across developed and emerging markets. The MSCI ACWI ex-US IMI Index is a free float-adjusted, market capitalization-weighted index that captures large, mid, and small cap representation across developed and emerging markets, excluding the U.S. The Value and Growth Indices are a subset of the Index that adopt a framework for style segmentation in which value and growth securities are characterized using different attributes. Multiple factors are used to identify value and growth characteristics. The MSCI ACWI Small Cap Index is a free float-adjusted, market capitalization-weighted index that captures small cap representation across developed and emerging markets. The MSCI Emerging Markets Index is a free float-adjusted, market capitalization-weighted index that is designed to measure the equity market performance of emerging markets. The MSCI World Index is a free float-adjusted, market capitalization-weighted index that is designed to measure the equity market performance of developed markets. The Bloomberg Barclays U.S. Aggregate Bond Index is a broad-based benchmark that measures the investment grade, U.S. dollar-denominated, fixed-rate taxable bond market, including Treasuries, government-related and corporate securities, mortgage-backed securities (agency fixed-rate and hybrid ARM pass-throughs), asset-backed securities and commercial mortgage backed securities. The Russell 2000 Index is a market capitalization-weighted index designed to represent the small cap segment of the U.S. equity universe. Index performance is for illustrative purposes only. The indices are unmanaged, do not incur fees or expenses, and cannot be invested in directly.

Alpha is a measure of an investment's return in excess of the market's return, after both have been adjusted for risk.

Half-life is a statistical measure of the time required for the discrepancy between price and value to contract by half of its starting value. Fundamental value estimates are based on the Dynamic Allocation Strategies team's proprietary research.

P/E Ratio is a measure of valuation which compares share price to earnings per share, calculated using estimates for the next twelve months.

Standard deviation is a statistical measurement of variations from the average.


The William Blair Earnings Trend Model captures information about short- and medium-term changes in analyst estimates in an attempt to anticipate future estimate changes and stock performance. The score combines measurements of earnings revisions, momentum, and earnings surprise.

The William Blair Valuation Model combines varying metrics used to characterize the relationship between the stock’s trading price and its intrinsic value. By going beyond using only one or two measures, the model attempts to build a more holistic version of a stock’s worth vis-a-vis the market. The score combines measurements of earnings/cash flow based, asset-based, and model-based factors.