Wrap buttons or secondary text in .panel-footer.
<!DOCTYPE HTML>
<html>
<head>
<link href="http://java2s.com/style/bootstrap.min.css" rel="stylesheet">
<!-- w w w.j a va 2 s .c o m-->
<script src="http://java2s.com/style/jquery-1.8.0.min.js"></script>
<script src="http://java2s.com/style/bootstrap.min.js"></script>
</head>
<body style='margin:20px;'>
<div class="panel">
Panel content
<div class="panel-footer">Panel footer</div>
</div>
</body>
</html>