The task of assisting health and mental health providers to deliver care for trauma survivors in ways that are consistent with current understanding of best practices in posttraumatic stress disorder assessment and treatment is an important public health priority. However, these providers face significant challenges in learning evidence-based interventions, keeping their knowledge current, and locating resources useful to their work. The Internet can provide a crucial element of more comprehensive training in empirically-supported practices and offer a useful means of shaping provider behavior and ensuring delivery of best practices. Dissemination is aided by effective training, ongoing consultation and coaching, monitoring of implementation, facilitative administrative support, and systems interventions; and the Internet can be used, to a greater or lesser extent, to support these various aspects of systematic implementation and knowledge management. Online training methods can offer many of the components of effective training, achieve some important instructional goals, and increase the cost-effectiveness and efficiency of in-person training. In addition, websites can support communities of practice, assist with preparation for dissemination projects, facilitate measurement of practitioner needs, preferences, and practices, make evidence-based practices easier to use, create better-informed clients, and enable clinicians and managers to more rapidly and efficiently locate the information they require.