In conjunction with vendor independence and reusability of information, it is necessary to define a universal company-wide view of decision-orientated information with established standards. Referring to heterogeneous components within a BI solution, standards play especially a major role for interchange and access of metadata or data which reside in another vendor’s product. In general, standards increase the potential utilisation of corporate data and metadata at all. Basic requirements for integration of company-wide data are the combination of syntactical and semantical information into a universal metamodel. A standardised reference model guarantees the reduction of modelling effort and realise simultaneously a high data quality. This section focuses on the present state of the metamodel standards representing complete BI solutions: the Common Warehouse Metamodel (CMW) and the Open Information Model (OIM).