Are you using online or desktop?

Desktop - backup to some external device, at least daily, at least 1 external device. 

Online - I don't know. Presumably it is continually backed up.  

And during tax season... I back up a.m. & p.m.   I take the external back-up home with me; depending on my level of paranoia I may even sleep with it under my pillow.

You *can* set Lacerte to save your keypunching every few minutes (somewhere in settings...) so you don't lose your immediate work.  The shorter the "save" time, the slower the program seems to run (in my experience, YMMV).

BUT that doesn't NOT save the client file anywhere, in case of a hard drive failure.

Carbonite is touted as a good one to use to back up to the *cloud*.

Yes, data input is saved automatically by PTO on a continuous basis.  Intuit also maintains redundant backup of the data for their benefits, not yours.  If you accidentally delete a return, however, Intuit is under no obligation to restore the data for you even if an old backup is available.

@itonewbie Is this true for Lacerte via Real Networks? Can they even do an external backup?

Yes, my understanding is that it is possible.  With the hosting solution, the subscriber still owns the data, which is unlike PTO.  The hosting solution merely provides a platform in the cloud to host the program and data.

https://proconnect.intuit.com/lacerte/faqs-hosting/

Your data will be saved when you close the return. There is also an autosave feature in options. Use it.

Note-this saves the data on your computer/network only.