diff --git a/service/ptos/head/mm/vad.h b/service/ptos/head/mm/vad.h
new file mode 100644
index 0000000..060f433
--- /dev/null
+++ b/service/ptos/head/mm/vad.h
@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2026, Chloe M.
+ * Provided under the BSD-3 clause.
+ *
+ * Description: Virtual address descriptor management
+ * Author:      Chloe M.
+ */
+
+#ifndef _MM_VAD_H_
+#define _MM_VAD_H_ 1
+
+#include <ptdef.h>
+#include <mm/vmm.h>
+#include <tree.h>
+
+/*
+ * A virtual address descriptor represents a single page
+ * of memory that can be allocated.
+ *
+ * @Range:      Virtual memory range this covers
+ * @TreeLink:   Red-black tree link
+ */
+typedef struct _MM_VAD {
+    MM_RANGE Range;
+    RB_ENTRY(_MM_VAD) TreeLink;
+} MM_VAD;
+
+/*
+ * A virtual address descriptor tree lists a collection
+ * of virtual address descriptors in an ordered manner.
+ *
+ * @Head:       Head of the red-black tree
+ * @Elements    Number of elements in red-black tree
+ */
+typedef struct {
+    RB_HEAD(VadTree, _MM_VAD) Head;
+    USIZE Elements;
+} MM_VAD_TREE;
+
+#endif  /* !_MM_VAD_H_ */