diff --git a/sessions.go b/sessions.go
index <HASH>..<HASH> 100644
--- a/sessions.go
+++ b/sessions.go
@@ -45,7 +45,10 @@ func NewSession(store Store, name string) *Session {
 
 // Session stores the values and optional configuration for a session.
 type Session struct {
-	ID      string
+	// The ID of the session, generated by stores. It should not be used for
+	// user data.
+	ID string
+	// Values contains the user-data for the session.
 	Values  map[interface{}]interface{}
 	Options *Options
 	IsNew   bool
[docs] Document Session.ID more clearly (#<I>) (#<I>)