The integration of geographic information systems (GIS) and building information modelling (BIM) promises enormous potential for optimizing construction projects over their entire life cycle. By combining large-scale geographic data with detailed building models, more informed decisions can be made, processes can be designed more efficiently and innovative solutions can be developed. In practice, however, the integration and use of synergy effects is often more complex than expected. Clients often lack the know-how to integrate GIS-specific aspects into a BIM-compatible tender and to develop suitable Employer Information Requirements (EIR). As a result, the integration of GIS data is often not given sufficient consideration in the planning and execution of construction projects. Typical difficulties include insufficiently described input data, incorrect georeferencing or unclear integration strategies. The recommendations for the integration of GIS data in BIM projects presented in the lecture are the result of an intensive discussion of the buildingSMART specialist group "BIM and GIS integration" and show how the challenges described can be met with the help of the Employer Information Requirements (EIR)