William Blair International Growth Fund
Earns 2010 Lipper Fund Award

The William Blair International Growth Fund - Class I Shares has been ranked the “Number One” Fund in the International Multi-Cap Growth Category for the 10-year period ending December 31, 2009 in the Lipper Fund Awards 2010.

The William Blair International Growth Fund – Class I Shares received a Lipper Performance Achievement Certificate for Consistent Return which topped its Lipper International Multi-Cap Growth Category peer group for the 10-year period ending December 31, 2009. The Fund posted the best performance results out of 29 funds in the International Multi-Cap Growth Category for this 10-year period.

The Lipper Fund Awards recognize funds that have excelled in delivering consistently strong risk-adjusted performance, relative to peers. The Lipper Fund Awards are formally announced each year at ceremonies which take place in 21 countries in Asia, Europe, MENA, and the Americas.

Lipper Fund Awards are part of the Thomson Reuters Awards for Excellence, a global family of awards that celebrate exceptional performance throughout the professional investment community. The Thomson Reuters Awards for Excellence recognize the world's top funds, fund management firms, sell-side firms, research analysts, and investor relations teams.

We congratulate the William Blair International Team on this significant achievement!

William Blair International Growth Fund Earns 2010 Lipper Fund Award

Performance cited represents past performance. Past performance does not guarantee future results and current performance may be lower or higher than the data quoted. Investment returns and principal will fluctuate and you may have a gain or loss when you sell shares. Class I Shares are available only to investors who meet certain eligibility requirements.

The International Multi-Cap Growth Funds Lipper Classification is for the 10-year risk adjusted performance among 29 eligible International Multi-Cap Growth Funds for the period ended Dec. 31, 2009. Fund classification averages are calculated with all eligible share classes for each eligible classification. The calculation periods extend over 36, 60, and 120 months. The highest Lipper Leader for Consistent Return (Effective Return) value within each eligible classification determines the fund classification winner over three, five, or ten years. The William Blair International Growth Fund’s Rank (Class I Shares) and the number of Funds in the Category for 3 years was 61/86; for five years, 48/60.

International investing involves special risk considerations, including currency fluctuations, lower liquidity, economic and political risk. Investing in emerging markets can increase these risks.