The document discusses the importance of content in newsletters and how to develop and maintain quality content over time. It notes that content is king and must provide deep, up-to-date information to readers. The document provides suggestions for coming up with content ideas such as responding to customers, repackaging expertise, and reflecting one's world. It also offers tips for keeping content production on track even when busy, such as making lists, using a content calendar, and recycling or stretching existing content. Finally, it reviews common mistakes like producing content that is boring, wandering, contains spelling errors, or is ill-fitting for its context.