Although there's no standard definition for an environmentally responsible office, most people would define it in common sense terms: a work space that uses the least amount of energy and other resources, creates the least amount of waste, and provides a healthy environment for the people working there.

The idea that being green requires untold expense and inconvenience is a fallacy born of stereotypes: that environmental responsibility in business (or in life) demands doing without, sacrificing convenience, and buying premium-priced products that may be inferior to their conventional (and cheaper) countertypes. True, there are some poor-quality, pricey green products out there, but that's no different from the rest of the marketplace.

In reality, "green" can often mean better, and sometimes cheaper. In the case of offices, going green can cut costs, improve efficiency, and create more pleasant—and sometimes more productive—workplaces. Some, but not all, activities may require making financial investments that pay themselves back over time, but many of the changes are free, requiring mostly operational and behavioral changes. Of course, that's easier said than done.

Here are the three categories of environmental improvements with the biggest bang for the buck. Some of these can be done by individuals; others require organizational involvement.

1. Energy and Lighting. Commercial buildings consume more than one third of all energy generated in the U.S. and energy use is the largest operating expense (about one third of the budget) of commercial office buildings. There are myriad ways to use energy more efficiently. First and foremost is lighting. Fluorescent and LED (light-emitting diode) bulbs not only provide more lumens per watt but also produce less heat, thereby reducing air conditioning costs. Newer electronic transformers and ballasts that run tube-type fluorescent bulbs are far more efficient than older electromagnetic fluorescents. Bonus: they also eliminate the bulbs' annoying flicker. According to a recent study by the Canadian government, the annual operating cost for a standard two-lamp electronic fixture costs $2.89 Canadian (about $2.26 USD) a year per square meter, compared with $5.29 Canadian ($4.14 USD) for conventional fluorescents. Based on those figures, a 50,000-square-foot (4,645-square-meter) building with efficient lighting would save $11,148 a year ($8,720 USD) in energy costs. Adding occupancy sensors, which turn lights off when no one's around, and other lighting controls can cut costs even further.

Of course, there are all those machines: computers, printers, modems, telephones, fax machines, scanners…. Many remain powered up 24/7, despite the fact that they're used only a few hours (or minutes) a day. Look for Energy Star computers, which must meet strict energy-efficiency requirements developed by the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy (DoE). Buying an Energy Star computer helps save energy by 70 percent over conventional models and could save up to $50 annually per machine.

To maximize those savings, plug office machines into a power strip that can be turned off (or will switch off automatically); the transformers in most machines' AC adapters draw power continuously, even when the machines are not in use, or even when they're not plugged into the adapter. And don't rely on computers' screen savers to save energy—they don't.

2. Paper Use. Reducing paper use is a no-brainer, when you consider paper's real cost. A study by the Environmental Defense Fund (EDF) and Citigroup estimated that the real  price tag of a $2 ream of office paper is 31 times that—$62—when you add in the costs of paper storage, printing, copying, recycling, disposal and postage. So, saving paper has a multiplier effect—and not just financially: The pulp and paper industry is the second-largest consumer of energy in the U.S. and uses more water to produce a ton of product than any other industry.

There are countless paper-saving tips, starting with the obvious: Don't print unless you must. If you do print, use both sides of the page or print drafts on the blank side of already printed documents.

Whatever paper you do use, recycle if possible. Recycling white and mixed office paper can be profitable. It eliminates waste-disposal costs, as many recyclers will haul the paper for free, because they can resell it in recycling markets. A 150-person office can generate 23 tons of the stuff in the course of a year, saving up to $3,900, according to a 2000 study by a New York City government agency, although prices fluctuate over time and from region to region.

3. Travel and Commuting. Getting to and from work or traveling to business meetings represents the biggest part of some companies' environmental footprint, in terms of the energy used and pollution generated. In the U.S., roughly a third of total greenhouse gas emissions stem from automobile, air, train and bus travel. Both business travel and employee commuting represent opportunities to save time and money.

For example, telecommuting—allowing select employees to work from home or other locations all or part of the time—can save employees' time and cut their commuting costs, and it can also reduce real estate costs. The cost of operating a computer and a broadband line from home is considerably cheaper than the tab for an office cubicle. Employees might be happier and more productive, too—between 10 and 20 percent more productive, according to several recent studies. For example, a 2004 study by AT&T found that a company could eliminate one office for every three teleworkers, a savings of about $2,000.

Cutting business travel is another potential source of savings. A new generation of "telepresence" technologies is enabling even smaller companies to "meet" long distance with others. Portable telepresence equipment that can fit on a conference table now costs around $5,000, a tab quickly offset by the expensive biz trips avoided.

Joel Makower is the executive editor of and author of Strategies for the Green Economy: Opportunities and Challenges in the New World of Business.