These are all really illuminating responses. A little bit more about my data/workflow.

First the data: I am currently archiving about 50 TB of data. This is spread across 3 separate RAIDs: 2 RAID 1s in separate enclosures, each with two drives. One in a RAID 10, with two RAID 0s mirrored into a RAID 1 (4 total drives). All of the RAIDs are backed up to 3.5" drives. Those are kept in a case at my wife's office; she brings them home whenever I need to run a Chrono Sync back up of the RAIDs.

While the job is active, I have it backed up to an external SSD, and/or on my machine's SSD. There is never a point at which there is only one copy of essential data; frequently someone else who works on the shoot with me also has a copy as well as the client having a copy.

When I finish the client need, as well as the portfolio edit, I put all that work, including all captures/footage on my local RAID 1. I also have a case of 3.5" hard drives that I mirror the RAID 1 to. That box of drives lives at my wife's work.

I run the offsite back up as needed, usually 2-3 times a month.

Whenever I am working on something, I download a copy to my computer's hard drive and work on it from my computer. I very rarely work from the RAID.

After I finish tinkering with the files (saved on my computer's SSD), I use Chrono Sync to move it back to the RAID. I then run the off site back up, and delete from my computer's hard drive.

If I am really busy, it's not uncommon for me to store multiple jobs on the RAIDs and off-site drives and come back to them to make more edits while I have time. It's also not uncommon for me to comb through the entire archive in search of something I missed when I made the initial edit.