This Technical Specification (CEN/TS 16157-3) specifies and defines component facets supporting the exchange and shared use of data and information in the field of traffic and travel. The component facets include the framework and context for exchanges, the modelling approach, the data content, the data structure and relationships and the communications specification. This Technical Specification is applicable to: traffic and travel information which is of relevance to road networks (non urban and urban); public transport information that is of direct relevance to the use of a road network (e. g. road link via train or ferry service). This Technical Specification establishes specifications for data exchange between any two instances of the following actors: Traffic Information Centres (TICs); Traffic Control Centres (TCCs); Service Providers (SPs). Use of this Technical Specification may be applicable for use by other actors. This Technical Specification includes the following types of information content: road traffic event information - planned and unplanned occurrences both on the road network and in the surrounding environment; operator initiated actions; road traffic measurement data, status data and travel time data; travel information relevant to road users, including weather and environmental information; road traffic management information and instructions relating to use of the road network. This part of the CEN/TS 16157 specifies the informational structures, relationships, roles, attributes and associated data types required for publishing situation traffic and travel information within the DATEX II framework. This is specified as a DATEX II Situation Publication sub-model which is part of the DATEX II platform independent model, but this Part excludes those elements that relate to location information which are specified in CEN/TS 16157-2 and those elements that relate to VMS settings which are specified in Part 4 of CEN/TS 16157.