UPO and a set of ontologies for processes and organizations. Most of the ontologies are written in WSML, and some are also written in OCML. A candidate model for the UPO was DDPO (DOLCE+DnS Plan Ontology), a planning ontology which specifies plans and distinguishes between abstract and executable plans. DOLCE (Descriptive Ontology for Linguistic and Cognitive Engineering) aims at capturing the ontological categories underlying natural language and human commonsense. DnS (Descriptions and Situations), is a constructivist ontology that allows for context-sensitive redescriptions of the types and relations postulated by other given ontologies (or ground vocabularies). Together in DDPO, DOLCE and DnS are used to build a Plan Ontology that includes physical and non-physical objects (social entities, mental objects and states, conceptualizations, information objects, constraints), events, states, regions, qualities, and constructivist situations. The main target of DDPO is tasks, namely the types of actions, their sequencing, and the controls performed on them. oXPDL The ontology oXPDL is a process interchange ontology based on the standardised XML Process Definition Language (XPDL). The purpose of oXPDL is to model the semantics of XPDL process models in standardized Web ontology languages such as OWL and WSML, while incorporating features of existing standard ontologies such as PSL, RosettaNet, and SUMO. GFO The General Formal Ontology (GFO) is an ontology integrating processes and objects. GFO includes elaborations of categories like objects, processes, time and space, properties, relations, roles, functions, facts, and situations. GFO allows for different axiomatizations of its categories, such as the existence of atomic time-intervals vs. dense time. Two of the specialties of GFO are its account of persistence and its time model. Regarding persistence, the distinction between endurants (objects) and perdurants (processes) is made explicit within GFO by the introduction of a special category, a persistant. A persistant is a special category with the intention that its instances "remain identical" over time. With respect to time, time intervals are taken as primitive in GFO, and time-points (called "time boundaries") are derived. Moreover, time-points may coincide, which is convenient for modelling instantaneous changes. m3po and m3pl The multi metamodel process ontology (m3po) combines workflows and choreography descriptions so that it can be used as a process interchange ontology. For internal business processes, Workflow Management Systems are used for process modelling and allow describing and executing business processes. For external business processes, choreography descriptions are used to describe how business partners can cooperate. A choreography