diff --git a/docs/getting_started/build-options.rst b/docs/getting_started/build-options.rst
index 585b2a1..d2cda4d 100644
--- a/docs/getting_started/build-options.rst
+++ b/docs/getting_started/build-options.rst
@@ -973,6 +973,11 @@
   functions that wait for an arbitrary time length (udelay and mdelay). The
   default value is 0.
 
+- ``ENABLE_BRBE_FOR_NS``: This flag enables access to the branch record buffer
+  registers from NS ELs when FEAT_BRBE is implemented. BRBE is an optional
+  architectural feature for AArch64. The default is 0 and it is automatically
+  disabled when the target architecture is AArch32.
+
 - ``ENABLE_TRBE_FOR_NS``: This flag is used to enable access of trace buffer
   control registers from NS ELs, NS-EL2 or NS-EL1(when NS-EL2 is implemented
   but unused) when FEAT_TRBE is implemented. TRBE is an optional architectural