Index: head/en_US.ISO8859-1/books/handbook/advanced-networking/chapter.xml
===================================================================
--- head/en_US.ISO8859-1/books/handbook/advanced-networking/chapter.xml
+++ head/en_US.ISO8859-1/books/handbook/advanced-networking/chapter.xml
@@ -893,6 +893,27 @@
 ath0: [ITHREAD]
 ath0: AR2413 mac 7.9 RF2413 phy 4.5</screen>
       </sect3>
+
+      <sect3>
+	<title>Setting the Correct Region</title>
+
+	<para>Since the regulatory situation is different
+	  in various parts of the world, it is necessary to
+	  correctly set the domains that apply to your location to
+	  have the correct information about what channels can be
+	  used.</para>
+
+	<para>The available region definitions can be found in
+	  <filename>/etc/regdomain.xml</filename>.  To set the data at
+	  runtime, use <command>ifconfig</command>:</para>
+
+	<screen>&prompt.root; <userinput>ifconfig <replaceable>wlan0</replaceable> regdomain <replaceable>ETSI</replaceable> country <replaceable>AT</replaceable></userinput></screen>
+
+	<para>To persist the settings, add it to
+	  <filename>/etc/rc.conf</filename>:</para>
+
+	  <screen>&prompt.root; <userinput>sysrc create_args_wlan0="country <replaceable>AT</replaceable> regdomain <replaceable>ETSI</replaceable>"</userinput></screen>
+      </sect3>
     </sect2>
 
     <sect2>