Anapproachtosupportinguserinterfacesusinganattributegrammarcombinedwithaneventmodelisdescribed.Themainemphasisishowtorepresentamulti-threaddialoguemodelindirectmanipulationuserinterfaces.Itisshownthatcontrolsequencewithindialogues,communicationwithotherdialogues,andsomecomputationsforapplicationscanbespecifiedwithasyntacticandsemanticnotation.Theattributegrammarspecificationcanbeimplementedusinganattributegrammarintepreterembeddedintherun-timestructuresupportingcommunication,synchronization,anddialogueexecuton.