(FORTUNE Small Business) – Back in the 1980s, real investors used to snigger at socially responsible investing (SRI). Who were those do-gooders kidding? Gunmakers, tobacco companies, and environment despoilers wouldn't miss a beat, much less reform their nasty habits, just because a few righteous investors wouldn't buy their stock. And SRI returns? Putting a halo on your portfolio proved painful.

But now those real investors are swallowing their smirks. The idea of using your money to reflect and advance your values has had unmistakable appeal, driving SRI assets to more than $2 trillion by the end of 2001, up from $639 billion in 1995, according to the Social Investment Forum. What's more, contrary to expectations, SRI's returns have been excellent. The Domini 400 Social Index advanced an average 13.77% in the past ten years while Standard & Poor's 500 index grew 12.95%. So does investing with a conscience give you a strategic edge? Not really. But it's nice to know that you don't have to lose out on returns while you gain in integrity. Here are SRI's three key components and how to play them.

SCREENING The most obvious way to express your beliefs is to shun the stocks of companies whose practices or products you disapprove of. If you buy your own stocks and bonds, implementing your criteria is easy. But if you want help constructing a portfolio--or would like to introduce SRI into your employees' 401(k) options--you can find financial planners, consultants, and brokers who specialize in SRI. Check out the Social Investment Forum's directory (www.socialinvest. org).

If you use mutual funds, investigate their definitions of SRI. For example, Green Century Balanced, the top-performing SRI fund for the past three years, with an average 17.5% return, dodges tobacco, defense, and weaponry stocks but seeks out companies whose products solve environmental problems.

ACTIVISM These socially responsible investors embrace missionary work. They buy the stock of an offending company and then wield shareholder clout by following their conscience in proxy votes. While your 200 Wal-Mart shares may not seem terribly persuasive, they count for a lot in the increasingly well-organized shareholder advocacy world. The Shareholder Action Network (www.shareholderaction.org), a clearinghouse of information on corporate reforms, helps disparate stockowners band together to promote corporate change. Past success: prodding Home Depot to stop using old-growth wood.

COMMUNITY INVESTMENT This is the orphan of the SRI movement. Few people think of treating their checking account and CDs as implements for social good, but you can by giving that business to a community-development bank or a community-development credit union. Both support development in low-income communities. Sound like a risky place to put your money? Deposits at community-development banks are FDIC-insured. Federal insurance covers deposits at community-development credit unions, which, just like conventional credit unions, are owned by their members. Find investments near you at the Calvert Social Investment Foundation (www.calvertfoundation.org).

Money talks, the old Wall Street axiom holds. Nowadays you can let yours speak volumes, and nobody's likely to snigger at your lack of investment savvy.