I work for a company that was audited for several months and it was a very stressful time for not only Quality and Regulatory, but for basically every department. It is a complete effort to comply with the demands of auditors and takes a lot of coordination with representatives of all business functions. From my understanding one of the lead auditors would ask for a particular document or information on a certain process and so the department leaders would need to search for it in the Quality System or hunt down a subject matter exist who may be the only person in the company who could answer that particular question. In the end, there were only some minor non-conformances to address. These can range from a missing form, to operators not following the steps of a Standard Operating Procedure, to poorly qualifying a supplier. Whichever the issue, the appropriate department would have to determine the corrective action to institute and prove the issue was fixed so it does not happen again in the future.