This guideline describes the requirements, in terms of contents and format, to be met by the documents that are to be drafted in the course of the processing of a BS project (planning, execution or operation of a BS system). The required contents and format of the documents to be drafted in the course of project processing for the relevant parties involved (building owners/orderers, architects, specialist planners, contractors, operators, etc.) are pointed out. Rather than introducing new terminology in the context of the drafting of documents, this guideline makes use of the existing terms, already used particularly in the VOB or the HOAI, although these terms are mostly not defined in greater detail. This guideline does not stipulate independent, new obligations to draft the documents. However, this guideline does not merely describe the information content and format of the documents in each planning or execution phase, i. e. from a vertical perspective, but it also shows the interfaces between the respective BS trades from a horizontal perspective. The following BS trades are considered by this guideline: - Sewage, water and gas systems - Heat supply systems - Ventilating and air-conditioning systems - Cooling systems - Power systems - Telecommunications and IT systems - Conveying systems - Building automation and control systems (BACS). The planning including the associated description shall be checked for compliance with the respective functional planning specifications, approved and accepted by the orderer at the end of each planning phase.