diff --git a/views/bootstrap/class.ViewDocument.php b/views/bootstrap/class.ViewDocument.php
index d4fda9bfd..d365d952d 100644
--- a/views/bootstrap/class.ViewDocument.php
+++ b/views/bootstrap/class.ViewDocument.php
@@ -323,36 +323,47 @@ class SeedDMS_View_ViewDocument extends SeedDMS_Bootstrap_Style {
 			return;
 
 		$accessop = $this->params['accessobject'];
-
 		if($accessop->check_controller_access('Download', array('action'=>'version'))) {
 			$latestContent = $document->getLatestContent();
-			switch($latestContent->getMimeType()) {
-			case 'audio/mpeg':
-			case 'audio/mp3':
-			case 'audio/ogg':
-			case 'audio/wav':
-				$this->contentHeading(getMLText("preview"));
+			$txt = $this->callHook('preDocumentPreview', $latestContent);
+			if(is_string($txt))
+				echo $txt;
+			else {
+				switch($latestContent->getMimeType()) {
+				case 'audio/mpeg':
+				case 'audio/mp3':
+				case 'audio/ogg':
+				case 'audio/wav':
+					$this->contentHeading(getMLText("preview"));
 ?>
 		<audio controls style="width: 100%;">
 		<source  src="../op/op.Download.php?documentid=<?php echo $document->getID(); ?>&version=<?php echo $latestContent->getVersion(); ?>" type="audio/mpeg">
 		</audio>
 <?php
-				break;
-			case 'application/pdf':
-				$this->contentHeading(getMLText("preview"));
+					break;
+				case 'application/pdf':
+					$this->contentHeading(getMLText("preview"));
 ?>
 			<iframe src="../pdfviewer/web/viewer.html?file=<?php echo urlencode('../../op/op.Download.php?documentid='.$document->getID().'&version='.$latestContent->getVersion()); ?>" width="100%" height="700px"></iframe>
 <?php
-				break;
-			case 'image/svg+xml':
-				$this->contentHeading(getMLText("preview"));
+					break;
+				case 'image/svg+xml':
+					$this->contentHeading(getMLText("preview"));
 ?>
 			<img src="../op/op.Download.php?documentid=<?php echo $document->getID(); ?>&version=<?php echo $latestContent->getVersion(); ?>" width="100%">
 <?php
-				break;
-			default:
-				break;
+					break;
+				default:
+					$txt = $this->callHook('additionalDocumentPreview', $latestContent);
+					if(is_string($txt))
+						echo $txt;
+					break;
+				}
 			}
+			$txt = $this->callHook('postDocumentPreview', $latestContent);
+			if(is_string($txt))
+				echo $txt;
+
 			if($converttopdf) {
 				$pdfpreviewer = new SeedDMS_Preview_PdfPreviewer($cachedir, $timeout);
 				if($pdfpreviewer->hasConverter($latestContent->getMimeType())) {