diff --git a/SUMMARY.md b/SUMMARY.md
index 7085289..49f8994 100644
--- a/SUMMARY.md
+++ b/SUMMARY.md
@@ -54,7 +54,8 @@
     * [Memblock](MM/linux-mm-1.md)
     * [Fixmaps and ioremap](MM/linux-mm-2.md)
     * [kmemcheck](MM/linux-mm-3.md)
-* [SMP]()
+* [Cgroups]()
+    * [Introduction](Cgroups/cgroups1.md)
 * [Concepts](Concepts/README.md)
     * [Per-CPU variables](Concepts/per-cpu.md)
     * [Cpumasks](Concepts/cpumask.md)