TOPIC: Are there any exceptions - remote panel wiring?

Are there any exceptions to the rule that remote panels (sub panels) should have neutrals and grounds separated, neutrals isolated from the remote panel and grounds bonded to the remote panel? 
3 wire/4 wire, or bonded by the conduit connecting the main and remote panels... 
Thank you for your help

Mike,
  There are some exceptions for detached buildings, but generally, No.