The quality of the cover letter is essential, as it is a roadmap to your petition and the place where the petitioner can provide narrative context for elements of the petition that may need explanation. Take care to go into detailed descriptions of what is included in your petition, and assume that the USCIS examiner does not have a comprehensive knowledge of the arts industry. In addition to providing an itemization of the contents of the petition, the cover letter should provide brief background information on the petitioner, background information on the individual or group, and details regarding the proposed activities.
Remember that the cover letter is your opportunity to make your case for the individual or group’s eligibility for O or P classification. The cover letter should ideally include excerpts of quotes from articles, background information on any awards and honors that will do not have obvious name recognition, thorough discussion of the events, etc.