diff --git a/build.sbt b/build.sbt
index ab6adad..612a321 100644
--- a/build.sbt
+++ b/build.sbt
@@ -18,7 +18,7 @@ ThisBuild / organization := "app.softnetwork"
 
 name := "notification"
 
-ThisBuild / version := "0.9.2"
+ThisBuild / version := "0.9-SNAPSHOT"
 
 ThisBuild / scalaVersion := scala212
 
diff --git a/common/src/main/protobuf/model/notifications.proto b/common/src/main/protobuf/model/notifications.proto
index 4f3e150..7f14b22 100644
--- a/common/src/main/protobuf/model/notifications.proto
+++ b/common/src/main/protobuf/model/notifications.proto
@@ -93,6 +93,10 @@ message Mail{
     repeated NotificationStatusResult results = 18;
     required NotificationType type = 19 [default = MAIL_TYPE];
     repeated Attachment attachments = 20;
+    // Story 13.7 — cross-service correlation id, set by the producer (e.g. license-server
+    // mailNotification) from the originating checkout/issuance flow. Read at send time to emit the
+    // notification_sent / notification_failed audit line. ScalaPB → correlationId: Option[String].
+    optional string correlation_id = 21;
 }
 
 message SMS{
@@ -112,6 +116,8 @@ message SMS{
     required NotificationStatus status = 17 [default = Pending];
     repeated NotificationStatusResult results = 18;
     required NotificationType type = 19 [default = SMS_TYPE];
+    // Story 13.7 — cross-service correlation id (see Mail.correlation_id).
+    optional string correlation_id = 20;
 }
 
 message Push{
@@ -136,6 +142,8 @@ message Push{
     required int32 badge = 22 [default = 0];
     optional string sound = 23;
     optional string application = 24;
+    // Story 13.7 — cross-service correlation id (see Mail.correlation_id).
+    optional string correlation_id = 25;
 }
 
 message Ws{
@@ -156,6 +164,8 @@ message Ws{
     repeated NotificationStatusResult results = 18;
     required NotificationType type = 19 [default = WS_TYPE];
     optional string channel = 20;
+    // Story 13.7 — cross-service correlation id (see Mail.correlation_id).
+    optional string correlation_id = 21;
 }
 
 message PushPayload{
diff --git a/common/src/main/scala/app/softnetwork/notification/model/Notification.scala b/common/src/main/scala/app/softnetwork/notification/model/Notification.scala
index c2b814d..30bbaa5 100644
--- a/common/src/main/scala/app/softnetwork/notification/model/Notification.scala
+++ b/common/src/main/scala/app/softnetwork/notification/model/Notification.scala
@@ -26,6 +26,12 @@ trait Notification extends State with NotificationDecorator {
 
   def results: Seq[NotificationStatusResult]
 
+  /** Story 13.7 — cross-service correlation id, set by the producer (e.g. license-server
+    * mailNotification) from the originating flow; read at send time to emit the audit line. Backed
+    * by the `optional string correlation_id` proto field on each notification message.
+    */
+  def correlationId: Option[String]
+
   def removeOnSuccess(): Option[Boolean] = None
 
   def removeAfterMaxTries(): Option[Boolean] = None
@@ -66,6 +72,8 @@ trait NotificationDecorator { _: Notification =>
     } else {
       recipients().mkString(",")
     }
+
+  def withCorrelationId(correlationId: String): Notification with NotificationDecorator
 }
 
 trait NotificationAckDecorator { _: NotificationAck =>
diff --git a/core/src/main/scala/app/softnetwork/notification/persistence/typed/NotificationBehavior.scala b/core/src/main/scala/app/softnetwork/notification/persistence/typed/NotificationBehavior.scala
index 058e087..489a8c8 100644
--- a/core/src/main/scala/app/softnetwork/notification/persistence/typed/NotificationBehavior.scala
+++ b/core/src/main/scala/app/softnetwork/notification/persistence/typed/NotificationBehavior.scala
@@ -12,6 +12,7 @@ import app.softnetwork.scheduler.message.SchedulerEvents.{
 }
 import app.softnetwork.scheduler.message.{AddSchedule, RemoveSchedule}
 import app.softnetwork.scheduler.model.Schedule
+import app.softnetwork.persistence.audit.AuditLog
 import app.softnetwork.persistence.now
 import app.softnetwork.persistence.typed._
 import app.softnetwork.notification.message._
@@ -45,6 +46,11 @@ trait NotificationBehavior[T <: Notification]
 
   private[this] val delay = 1
 
+  /** Story 13.7 — structured audit trail. service = "notification"; correlationId is threaded as
+    * data on the notification (proto field, exposed on the Notification trait), never via MDC.
+    */
+  private[this] lazy val audit: AuditLog = AuditLog("notification")
+
   /** Set event tags, which will be used in persistence query
     *
     * @param entityId
@@ -469,18 +475,30 @@ trait NotificationBehavior[T <: Notification]
       )
     Effect
       .persist(events)
-      .thenRun(_ =>
-        {
+      .thenRun(_ => {
+        // Story 13.7 — emit the terminal audit line, but only when an actual send/ack happened this
+        // round (skip deferred / already-sent no-ops, and the non-terminal Pending outcome). The
+        // correlation id rides the notification (proto field on the Notification trait); the channel
+        // is its NotificationType.
+        if (maybeAckWithNumberOfRetries.isDefined) {
+          val cid = updatedNotification.correlationId.getOrElse("-")
+          val channel = updatedNotification.`type`.name
           updatedNotification.status match {
-            case Rejected    => NotificationRejected(entityId, updatedNotification.results)
-            case Undelivered => NotificationUndelivered(entityId, updatedNotification.results)
-            case Sent        => NotificationSent(entityId, updatedNotification.results)
-            case Delivered   => NotificationDelivered(entityId, updatedNotification.results)
-            case _           => NotificationPending(entityId, updatedNotification.results)
+            case Sent | Delivered =>
+              audit.event(cid, "notification_sent", "channel" -> channel)
+            case Undelivered | Rejected =>
+              audit.event(cid, "notification_failed", "channel" -> channel)
+            case _ => // still pending — no terminal audit line yet
           }
         }
-        ~> replyTo
-      )
+        (updatedNotification.status match {
+          case Rejected    => NotificationRejected(entityId, updatedNotification.results)
+          case Undelivered => NotificationUndelivered(entityId, updatedNotification.results)
+          case Sent        => NotificationSent(entityId, updatedNotification.results)
+          case Delivered   => NotificationDelivered(entityId, updatedNotification.results)
+          case _           => NotificationPending(entityId, updatedNotification.results)
+        }) ~> replyTo
+      })
   }
 
 }
diff --git a/project/Versions.scala b/project/Versions.scala
index 24c73fe..f173e8d 100644
--- a/project/Versions.scala
+++ b/project/Versions.scala
@@ -6,9 +6,9 @@ object Versions {
 
   val logback = "1.4.14"
 
-  val genericPersistence = "0.8.5"
+  val genericPersistence = "0.9-SNAPSHOT"
 
-  val scheduler = "0.8.0"
+  val scheduler = "0.8-SNAPSHOT"
 
   val scalatest = "3.2.16"
 }
diff --git a/testkit/src/test/scala/app/softnetwork/notification/handlers/SimpleMailNotificationsHandlerSpec.scala b/testkit/src/test/scala/app/softnetwork/notification/handlers/SimpleMailNotificationsHandlerSpec.scala
index 74c5ae2..c63be10 100644
--- a/testkit/src/test/scala/app/softnetwork/notification/handlers/SimpleMailNotificationsHandlerSpec.scala
+++ b/testkit/src/test/scala/app/softnetwork/notification/handlers/SimpleMailNotificationsHandlerSpec.scala
@@ -3,6 +3,10 @@ package app.softnetwork.notification.handlers
 import app.softnetwork.notification.message._
 import app.softnetwork.notification.model.Attachment
 import app.softnetwork.notification.scalatest.SimpleMailNotificationsTestKit
+import app.softnetwork.persistence.audit.AuditLog
+import ch.qos.logback.classic.{Logger => LogbackLogger}
+import ch.qos.logback.classic.spi.ILoggingEvent
+import ch.qos.logback.core.read.ListAppender
 import org.scalatest.wordspec.AnyWordSpecLike
 import org.slf4j.{Logger, LoggerFactory}
 
@@ -142,6 +146,34 @@ class SimpleMailNotificationsHandlerSpec
       assert(probe.receiveMessage().schedule.uuid == s"MailNotification#$uuid#NotificationTimerKey")
     }
 
+    "emit a notification_sent audit line carrying the correlation id (Story 13.7)" in {
+      val cid = "notif-corr-13-7"
+      val auditLogger = LoggerFactory.getLogger(AuditLog.LoggerName).asInstanceOf[LogbackLogger]
+      val appender = new ListAppender[ILoggingEvent]()
+      appender.start()
+      auditLogger.addAppender(appender)
+      try {
+        val uuid = "auditedSend"
+        this ? (uuid, SendNotification(generateMail(uuid).withCorrelationId(cid))) await {
+          case n: NotificationSent => n.uuid shouldBe uuid
+          case _                   => fail()
+        }
+        // the emission runs in the behavior's thenRun BEFORE the reply, so it is captured by now
+        val sentLine =
+          appender.list.toArray.toList.collect { case e: ILoggingEvent => e }.find { e =>
+            val fields = e.getArgumentArray.map(_.toString).toSet
+            fields.contains("event_type=notification_sent") && fields.contains(
+              s"correlation_id=$cid"
+            )
+          }
+        assert(sentLine.isDefined, "expected a notification_sent audit line carrying the cid")
+        sentLine.get.getArgumentArray.map(_.toString) should contain("service=notification")
+      } finally {
+        auditLogger.detachAppender(appender)
+        appender.stop()
+      }
+    }
+
   }
 
 }