Mutual funds have grown in importance to U.S. households through the decades. Thirty years ago, only about 5 percent of households owned mutual funds. Now more than 40 percent do, according to the Investment Company Institute.

About 94 million people (43.6 percent of U.S. households) now own mutual funds. If that’s you, have you ever wondered who runs the funds you invest in?

There is the “investment adviser,” who makes investment decisions for the fund, and the “principal underwriter,” who arranges for the distribution (sale) of the fund’s shares to investors. And then you have the attorneys, accountants, printers and so on.

The question is, who’s in charge? The fund’s board of directors.

Mutual fund boards are not unlike other corporate boards; the standard of care is that of fiduciary — with the duty of loyalty to you, the person who owns the fund’s shares.

Unlike other boards, these must meet additional requirements set by federal law, such as the annual review of the fund’s contracts with the investment adviser and the principal underwriter.

Because of the potential for conflicts of interest, federal law also requires that a certain number of directors be independent of the adviser and underwriter. The director may not be an “interested person” who has personal, financial or professional relationships with the fund, investment adviser or principal underwriter.

As a mutual fund investor, you’ll know that most funds are not stand-alone operations. They are part of a complex, with multiple mutual fund offerings. While you might envision a separate board for each fund, that rarely occurs. Usually (87 percent of the time) a single “unitary board structure” oversees all the funds in the complex.

The larger complexes may have a “cluster structure,” with several boards overseeing a group of funds.

According to the Investment Company Institute, the median number of independent directors is six per complex. As of the end of 2016, the most recent data reported by the institute, 84 percent of the board seats were held by independent directors, representing eight independent directors per complex on average. Boards meet in person on average four to seven or more times a year.

The requirement that certain board members be independent is not common in business. These independent mutual fund directors serve as “watchdogs,” “providing independent oversight of the management of (mutual funds) to ensure that the (funds) are being operated in the interests of shareholders,” according to the institute’s “Report of the Advisory Group on Best Practices for Fund Directors.”

That should give mutual fund investors comfort.

For more information, read “Overview of Fund Governance Practices,” produced by the institute and Independent Directors Council. The institute is an association that represents mutual funds. The council represents the independent director community by advancing education, communication and policy positions of independent directors.

Julie Jason is a personal money manager at Jackson, Grant of Stamford, Conn., and an award-winning author. Contact her at readers@juliejason.com.