If you have an AJAX button in your form, a nice way of adding javascript is to use an IAjaxCallDecorator form.add(new AjaxButton("removeButton") { @Override protected IAjaxCallDecorator getAjaxCallDecorator() { return new AjaxPreprocessingCallDecorator(super.getAjaxCallDecorator()) { private static final long serialVersionUID = 1L; @Override public CharSequence preDecorateScript(CharSequence script) { return "if(!confirm('Are you sure you want to delete this?')) return false;" + script; } }; } }