EPA designated May as Environmental Science Month, and many of the activities have extended onward, with a Science Forum in Washington, DC, in June and video presentations-on air quality, coastal ecosystems, and water quality monitoring-still widely available. The forum included sessions on using monitoring data, consistent information, and “good science” to influence policy, and at this juncture few things could be more important for all of us involved with environmental issues to keep in mind. When it comes to the environment and its effects on human health, reports of risks tend to be alarming-sometimes alarmist-and too often are based on shaky or incomplete data. Policymakers as well as the public react to them. Exaggerated, oversimplified, and downright false claims not only do a disservice to the public but also, over time, inure people to problems they really should be concerned about. A tremendous number of these claims fall within the particular realm of ESC practitioners: there are frequent reports (and lawsuits) regarding water quality and air quality and the effects on everyone who swims, drinks water, or breathes. When your job involves preventing or repairing environmental damage, it’s almost inevitable that at some point you and your work will become part of the debate. Fortunately the ESC field has many tools and a strong history to support it. Serious research into the effects of erosion has been ongoing in the United States for nearly 80 years; USDA has maintained data on runoff and soil loss since the 1950s; the original Universal Soil Loss Equation to estimate annual soil loss was published in the 1960s and has been continually revised; and organizations like IECA provide education and coherence to the field. In addition, with urban runoff of greater concern and more heavily regulated than ever before, and with new products and technologies entering the market in record numbers, we have a growing system of checks and balances. Manufacturers’ claims for their products’ performance are being tested, some through the Environmental Technology Verification Program and others in independent laboratories across the country that specialize in ESC products and technologies. A body of evidence, no matter whose argument it’s being used to support, is rarely complete, final, and definitive. Back in 2001, when the National Academy of Sciences reviewed the proposed total maximum daily load (TMDL) program, it acknowledged some of the data were lacking, and it made many suggestions for improving the program, but, importantly, it also cautioned EPA and the states not to ‘wait until’ the science is complete,’which by its nature it never will be, before taking action. In almost any endeavor, from drug trials to vehicle crash tests to erosion and sediment control, there exists the same question of where to draw the line; the more information, the better the decision, but sooner or later, the FDA must approve or reject a new drug, new cars must roll off the assembly line, and a watershed protection plan or streambank restoration project must go forward based on the best research and evidence available. One of the greatest services ESC professionals can provide, beyond whatever practices we’re employing to prevent erosion and sedimentation to protect water quality, is to help separate the facts from the hype and determine what’s really meant by “scientific evidence shows…” when the statement is applied to a product claim or political argument.