Veliki Brat 2011 (commonly known as Veliki Brat 4 or VB4 for short) was the fourth season of the Serbian production of the Big Brother reality television series Veliki Brat. This season was notable for being the first to feature houseguests from Croatia, and in doing so it holds the record for largest number of unique nations represented with five. Along with Serbia and Croatia, the other three nations represented were Montenegro, Bosnia and Herzegovina, and North Macedonia. The program is known as Big Brother in Croatia due to a former Croatian Big Brother series that aired for five seasons which was not affiliated with Veliki Brat.