This document discusses the elements and requirements of effective advertising letters. It defines advertising letters as a direct form of marketing similar to personal salesmanship. Key requirements for advertising letters include knowing your product and target audience, using an engaging layout with headlines and storytelling language, being honest, and proofreading for errors. Effective letters also include personalized and short sentences to capture attention. Elements that make up an advertising campaign include the mailing envelope, letter, brochures, response forms, and reply envelopes. Examples from the 1960s are also provided to illustrate best practices. Planning, keeping messages concise and focused on customer benefits are emphasized for response.