American Association for the Advancement of Science
The American Association for the Advancement of Science has put together excellent resources about communicating science. They also offer various webinars on the topic, which can be found at http://membercentral.aaas.org/multimedia/webinars
Scientists and engineers often find that they need to discuss complicated scientific findings in a clear, concise manner with members of the public. The AAAS Communicating Science workshops developed by the Center for Public Engagement with Science and Technology are specifically designed to address the needs of scientists and engineers in communicating scientific information to those outside their immediate field.
The ability to convey complex concepts effectively can help scientists successfully engage in a variety of public and professional interactions, including conducting media interviews, writing grant proposals, discussing ideas with students, testifying before Congress, or participating in a public forum.