diff --git a/preserves.md b/preserves.md
index 30ebf7a..e9d9845 100644
--- a/preserves.md
+++ b/preserves.md
@@ -215,6 +215,14 @@ equivalent compact machine-readable syntax.
     `null` are all read as `Symbol`s, and that `SignedInteger`s are
     never read as `Double`s.
 
+    The following [schema](./preserves-schema.html) definitions match
+    exactly the JSON subset of a Preserves input:
+
+        version 1 .
+        JSON = @string string / @integer int / @double double / @boolean JSONBoolean / @null =null
+             / @array [JSON ...] / @object { string: JSON ...:... } .
+        JSONBoolean = =true / =false .
+
 ### Character set.
 
 [ABNF][abnf] allows easy definition of US-ASCII-based languages.