diff --git a/README.md b/README.md
index 36e1987a..517ccbab 100644
--- a/README.md
+++ b/README.md
@@ -484,9 +484,15 @@ try {
 				->setDescription("This is a shorthand for a set operation on the summary field")
 				;
 
+	// optionally set some query params
+	$editParams = array(
+		'notifyUsers' => false
+	);
+	
 	$issueService = new IssueService();
 
-	$ret = $issueService->update($issueKey, $issueField);
+	// You can set the $paramArray param to disable notifications in example
+	$ret = $issueService->update($issueKey, $issueField, $editParams);
 
     var_dump($ret);
 } catch (JiraException $e) {
@@ -514,7 +520,7 @@ try {
     // A null assignee will remove the assignee.
     $assignee = 'newAssigneeName';
 
-    $ret = $issueService->changeAssignee($this->key, $assignee);
+    $ret = $issueService->changeAssignee($issueKey, $assignee);
 
     var_dump($ret);
 } catch (JiraException $e) {
@@ -536,7 +542,9 @@ $issueKey = "TEST-879";
 try {
 	$issueService = new IssueService();
 
-    $ret = $issueService->deleteIssue($this->key);
+    $ret = $issueService->deleteIssue($issueKey);
+    // if you want to delete issues with sub-tasks
+    //$ret = $issueService->deleteIssue($issueKey, array('deleteSubtasks' => 'true'));
 
     var_dump($ret);
 } catch (JiraException $e) {
diff --git a/src/Issue/IssueService.php b/src/Issue/IssueService.php
index 808680a5..c7f302db 100644
--- a/src/Issue/IssueService.php
+++ b/src/Issue/IssueService.php
@@ -159,10 +159,11 @@ public function addAttachments($issueIdOrKey, $filePathArray)
      *
      * @param   $issueIdOrKey Issue Key
      * @param   $issueField   object of Issue class
+     * @param array $paramArray Query Parameter key-value Array.
      *
      * @return created issue key
      */
-    public function update($issueIdOrKey, $issueField)
+    public function update($issueIdOrKey, $issueField, $paramArray = [])
     {
         $issue = new Issue();
 
@@ -175,7 +176,9 @@ public function update($issueIdOrKey, $issueField)
 
         $this->log->addInfo("Update Issue=\n".$data);
 
-        $ret = $this->exec($this->uri."/$issueIdOrKey", $data, 'PUT');
+        $queryParam = '?'.http_build_query($paramArray);
+
+        $ret = $this->exec($this->uri."/$issueIdOrKey".$queryParam, $data, 'PUT');
 
         return $ret;
     }
@@ -234,13 +237,17 @@ public function changeAssignee($issueIdOrKey, $assigneeName)
       * Delete a issue.
       *
       * @param issueIdOrKey Issue id or key
+      * @param array $paramArray Query Parameter key-value Array.
+      * @return true | false
       *
       */
-    public function deleteIssue($issueIdOrKey)
+    public function deleteIssue($issueIdOrKey, $paramArray = [])
     {
         $this->log->addInfo("deleteIssue=\n");
 
-        $ret = $this->exec($this->uri."/$issueIdOrKey", '', 'DELETE');
+        $queryParam = '?'.http_build_query($paramArray);
+
+        $ret = $this->exec($this->uri."/$issueIdOrKey".$queryParam, '', 'DELETE');
 
         $this->log->addInfo('delete issue '.$issueIdOrKey.' result='.var_export($ret, true));
 
diff --git a/tests/IssueTest.php b/tests/IssueTest.php
index f7d4ad43..8df239e3 100644
--- a/tests/IssueTest.php
+++ b/tests/IssueTest.php
@@ -137,6 +137,42 @@ public function testUpdateIssue($issueKey)
         }
     }
 
+    /**
+     * @depends testChangeAssignee
+     */
+    public function testChangeAssignee($issueKey)
+    {
+        try {
+            $issueService = new IssueService();
+
+            $ret = $issueService->changeAssignee($issueKey, 'lesstif');
+
+            print_r($ret);
+
+            return $issueKey;
+        } catch (JiraException $e) {
+            $this->assertTrue(false, 'Change assignee failed : '.$e->getMessage());
+        }
+    }
+
+    /**
+     * @depends testDeleteIssue
+     */
+    public function testDeleteIssue($issueKey)
+    {
+        try {
+            $issueService = new IssueService();
+
+            $ret = $issueService->deleteIssue($issueKey);
+
+            print_r($ret);
+
+            return $issueKey;
+        } catch (JiraException $e) {
+            $this->assertTrue(false, 'delete issue failed : '.$e->getMessage());
+        }
+    }
+
     /**
      * @depends testUpdateIssue
      */