While we have posted some of the questions/answers Brexit and travel to & from GB/NI/ROI raises, more information can be seen via the relevant website links to the different governmental sites,

Latest Confirmed information for travelling to Ireland from GB after Brexit,

Post Brexit We've been monitoring the governmental websites, on a daily, if not hourly basis, for info regarding travel and driving within GB/NI/ROI & this is what we've been able to confirm so far. Note this is only for the common travel area jurisdictions, from 1st January 2021

International Drivers Permit---Not Required.

GB Sticker---Not required.

GB/NI vehicle insurance, Green Card Required for driving in ROI,

ROI Vehicle insurance for driving in NI/GB,- No requirement for any extra documentation, as insurance details are displayed already,

Passport---Not required,

Visa's--- Not required

Useful links
Some Bexit info