The preselection is determined by the value of the property in the Bean - ie. if carsBean.car is a list of Cars then those that are present in that list will be 'pre-selected' in your selectManyCheckbox. You can use s:convertEntity but have a read of Chapter 28 of the Seam Reference manual first http://docs.jboss.com/seam/2.0.0.B1/reference/en/html/controls.html. You may also find s:selectItems easier than f:selectItems. <h:selectManyCheckbox id="cars" value="#{carsBean.car}"> | <f:selectItems value="#{carBean.carList}"/> | <s:convertEntity/> | </h:selectManyCheckbox> Cheers, Damian. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4069031#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...