Vegetated buffer strips (VBS) are often promoted as a management practice that farmers can use to help prevent the environmental effects of runoff. Reports in the literature suggest that VBS can be remarkably effective for phosphorous (P) and other farm sourced environmental contaminants. Some claim up to 90% of P can be stopped by VBS. But these are in controlled experiments. What happens in the real world? This study, conducted by ECOMatters Inc., set out to answer that question for cropped land in Manitoba. Vegetated buffer strips are not precisely defined. They are best described as a band of perennial vegetation between a cropped field and the surface drainage ditch or stream. The overall conclusion is that VBS do retain P, but putting them into practice for Manitoba farmers will be very difficult. Runoff happens mostly in spring during snowmelt, and usually is focused into a few spots along the edge of the field. A VBS running the length of the field will be mostly unused, but where the runoff happens, unless the VBS is expanded in width at this location, the VBS will be saturated and unable to fully meet the demand. Vegetated swales should be much more effective, because the runoff passes over a greater length of vegetated ground. A field-edge VBS will help in rainfall events, and will have some limited benefit for snowmelt. Perhaps more importantly is how the VBS is managed. To be most effective, the vegetation should be harvested at intervals, perhaps at least every few years. Burning the VBS probably completely erases any benefit, because the P in the ash will be especially easily carried by runoff.