Ok, this might be a bug... Everything on the page was always rendered, so that wasn't it. By process of elimination I identified the code causing the problem. This worked: (action method app.setTimecardWorker was called when item changed) | <h:outputLabel styleClass="textLabel2" for="worker">Worker</h:outputLabel> | <s:decorate> | <h:selectOneMenu id="worker" | value="#{timecardHome.instance.workerName}"> | <f:selectItems value="#{app.activeWorkers}" /> | <a4j:support event="onchange" | action="#{app.setTimecardWorker(timecardHome.instance)}" | reRender="rate" | ajaxSingle="true"/> | </h:selectOneMenu> | </s:decorate> | <h:outputLabel styleclass="textLabel2" for="rate">Rate $</h:outputLabel> | <s:decorate> | <h:inputText id="rate" | required="true" | size="3" | value="#{timecardHome.instance.hourlyRate}"/> | </s:decorate> | <h:outputLabel styleClass="textLabel2" for="hours">Hours</h:outputLabel> | <s:decorate> | <h:inputText id="hours" | required="true" | size="3" | value="#{timecardHome.instance.hours}"/> | </s:decorate> | <h:outputLabel styleclass="textLabel2" for="description">Description</h:outputLabel> | <s:decorate> | <h:inputText id="description" | required="true" | size="40" | value="#{timecardHome.instance.description}"/> | </s:decorate> | This didn't (no action method was called when same item was changed) | <h:outputLabel styleClass="textLabel2" for="worker">Worker</h:outputLabel> | <s:decorate> | <h:selectOneMenu id="worker" | value="#{timecardHome.instance.workerName}"> | <f:selectItems value="#{app.activeWorkers}" /> | <a:support event="onchange" | action="#{app.setTimecardWorker(timecardHome.instance)}" | reRender="rate" | ajaxSingle="true"/> | </h:selectOneMenu> | </s:decorate> | <h:outputLabel styleclass="textLabel2" for="rate">Rate $</h:outputLabel> | <s:decorate> | <h:inputText id="rate" | required="true" | size="3" | value="#{timecardHome.instance.hourlyRate}"/> | </s:decorate> | <h:outputLabel styleClass="textLabel2" for="month">Month</h:outputLabel> | <s:decorate> | <h:selectOneMenu id="month" | converter="#{monthconverter}" | value="#{timecardHome.instance.month}"> | <f:selectItems value="#{app.months}" /> | </h:selectOneMenu> | </s:decorate> | <h:outputLabel styleClass="textLabel2" for="hours">Hours</h:outputLabel> | <s:decorate> | <h:inputText id="hours" | required="true" | size="3" | value="#{timecardHome.instance.hours}"/> | </s:decorate> | <h:outputLabel styleclass="textLabel2" for="description">Description</h:outputLabel> | <s:decorate> | <h:inputText id="description" | required="true" | size="40" | value="#{timecardHome.instance.description}"/> | </s:decorate> | It seems adding the second select list did something to interfere with a4j:support calling the action method on the first select list. Bizarre! Any clues? Greg View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4034787#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...