diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2acf5e1..9eaec3c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,9 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [3.1.1] - 2024-05-31
+- Added `proof_of_delivery` field to Tracking Model.
+
 ## [3.1.0] - 2024-01-03
 - All SDK errors will be wrapped with "APIError".
 
diff --git a/trackings.go b/trackings.go
index 4a9141d..23f0fc6 100644
--- a/trackings.go
+++ b/trackings.go
@@ -498,6 +498,13 @@ type Tracking struct {
 	 * If a shipment has multiple carriers, you can use the next_couriers field to tell AfterShip who the second carrier is.
 	 */
 	NextCouriers []NextCourier `json:"next_couriers"`
+
+	ProofOfDelivery []ProofOfDelivery `json:"proof_of_delivery"`
+}
+
+type ProofOfDelivery struct {
+	Type string `json:"type"`
+	Url  string `json:"url"`
 }
 
 type NextCourier struct {
diff --git a/version.go b/version.go
index 76a0ac0..3acf17c 100644
--- a/version.go
+++ b/version.go
@@ -1,4 +1,4 @@
 package aftership
 
 // VERSION is the version number of this package
-const VERSION string = "3.1.0"
+const VERSION string = "3.1.1"