February is often manager-musical-chairs month at Vanguard, and since I wrote about Earl McEvoy's retirement, Vanguard has announced more manager changes. Subscribers to my newsletter can read my full analysis on these management changes in the news section of my website, but here's an overview.

First, Vanguard ousted Grantham, Mayo, Van Otterloo, which manages some $150 billion in assets and is the home of noted perma-bear Jeremy Grantham. The quantitative group had originally been brought into Vanguard to run a piece of Explorer in the spring of 2000 (but wasn't handed a piece of the Small Company Growth Annuity until the fall), then were the founding managers of U.S. Value when it debuted in June 2000. Vanguard's own quantitative equity team will replace GMO.

The GMO firing raises, once again, the question of whether Vanguard's disclosures are adequate or accurate. In U.S. Value's September 2007 annual report, published in November, just three months ago, Vanguard's Board says that retaining GMO is "in the best interests of the fund and its shareholders." Could they have changed their tune so quickly as to turn around and fire GMO just a few months later?

Vanguard also announced that International Growth is adding a third manager—M&G Investment Management, which has run Precious Metals & Mining since its inception. The question we have to ask here is, will the addition of another management team turn it into an index-hugging foreign fund?

As I've always said, when it comes to mutual funds, you're not just buying a fund, you're hiring the manager. That's why monitoring changes in fund management and knowing the long-term track record of managers is one of my top priorities, and should be yours, too.