The 7 Cs of business writing are:
1. Completeness - Answer all questions fully using the 5Ws and 1H.
2. Conciseness - Be focused and avoid unnecessary words.
3. Consideration - Focus on the reader's needs and use a positive tone.
4. Clarity - Use simple, familiar language and effective structure.
5. Concreteness - Provide specific details, facts, and vivid descriptions.
6. Courtesy - Be sincere, tactful and avoid language that could offend.
7. Correctness - Ensure accurate information and proper writing mechanics.