diff --git a/chapter04/creatingminlayout.xml b/chapter04/creatingminlayout.xml
index 41ec2b7f0..c709c8ed3 100644
--- a/chapter04/creatingminlayout.xml
+++ b/chapter04/creatingminlayout.xml
@@ -8,7 +8,7 @@
 <sect1 id="ch-tools-creatingminlayout">
   <?dbhtml filename="creatingminlayout.html"?>
 
-  <title>Creating a limited directory layout in LFS filesystem</title>
+  <title>Creating a Limited Directory Layout in the LFS Filesystem</title>
 
   <para>In this section, we begin populating the LFS filesystem with the
   pieces that will constitute the final Linux system. The first step is to
@@ -46,4 +46,16 @@ ln -sv usr/libx32 $LFS/libx32</userinput></screen>
 
 <screen><userinput>mkdir -pv $LFS/tools</userinput></screen>
 
+  <note>
+    <para>
+      The LFS editors have deliberately decided not to use a
+      <filename class="directory">/usr/lib64</filename> directory.  Several
+      steps are taken to be sure the toolchain will not use it. If for any
+      reason this directory appears (either because you made an error in
+      following the instructions, or because you installed a binary package that
+      created it after finishing LFS), it may break your system.
+      You should always be sure this directory does not exist.
+    </para>
+  </note>
+
 </sect1>
diff --git a/chapter07/creatingdirs.xml b/chapter07/creatingdirs.xml
index c242f0464..a95f3bd57 100644
--- a/chapter07/creatingdirs.xml
+++ b/chapter07/creatingdirs.xml
@@ -71,6 +71,17 @@ install -dv -m 1777 /tmp /var/tmp</userinput></screen>
     directories that are really necessary. However, feel free to create more
     directories, if you wish.  </para>
 
+  <warning>
+    <para>
+      The FHS does not mandate the existence of the directory
+      <filename class="directory">/usr/lib64</filename>, and the LFS editors
+      have decided not to use it. For the instructions in LFS and BLFS to work correctly,
+      it is imperative that this directory be non-existent. From time to time you should
+      verify that it does not exist, because it is easy to create it
+      inadvertently, and this will probably break your system.
+    </para>
+  </warning>
+
   </sect2>
 
 </sect1>