This document provides tips for writing an effective business letter. It explains that a business letter communicates professionally between companies to address issues or agendas. Key tips include knowing your audience to craft an engaging message and using a clear structure. Writers should keep the letter concise and simple while maintaining a formal yet conversational tone. Thorough proofreading is important to eliminate errors that could undermine the message. An effective business letter is complete in providing all necessary information to the reader.