Introduction: Yard maintenance equipment is potentially dangerous, and some of the more frequency used equipment (e.g., lawn mowers) has been extensively studied. However, the extent of lawn trimmers as a source of injury has not previously been explored. Methods: Data from the Consumer Product Safety Commission's National Electronic Injury Surveillance System were used to estimate the number of patients treated in U.S. emergency departments for lawn trimmer-related injuries. Injury rates were calculated according to age, sex, and race, and characteristics of the injury event were determined. Results: An estimated 81,907 injuries involving a lawn trimmer occurred from 2000-2009. The incidence generally increased over time. Men, people aged 40-49, and Caucasians were the groups most likely to be injured. The most commonly injured body part was the head, specifically the eye, accounting for 42.5% of the injuries. Contusions and abrasions were the most common type of injury to the head, but lacerations were the most common injury to the extremities, and strains/sprains were the most common injury to the trunk. Discussion: Although previous research on lawn trimmers has focused exclusively on injuries to the eyes, the results of the current study show that such injuries are one component of the problem. Because most of the injuries were due to foreign objects, it is important that the use of adequate safety gear be emphasized when operating lawn trimmers. Impact on Industry: Results suggest that lawn trimmer design changes and better safety education for trimmer use can reduce the rate of injury and reverse the current trend. © 2012 National Safety Council and Elsevier Ltd. All rights reserved.