Automation systems for buildings interconnect components and technologies from the information technology industry and the telecommunications industry.In these industries,existing platforms and new platforms(that are designed to make building automation systems work) compete for market acceptance and consequently several platform battles among suppliers for building automation networking are being waged.It is unclear what the outcome of these battles will be and also which factors are important in achieving platform dominance.Taking the fuzziness of decision makers’ judgments into account,a fuzzy multi-criteria decision-making methodology called the Fuzzy Analytic Hierarchy Process is applied to investigate the importance of such factors in platform battles for building automation networking.We present the relative importance of the factors for three types of platforms(subsystem platforms,system platforms,and evolved subsystem platforms).The results provide a first indication that the set of important factors differs per type of platform.For example,when focusing on other stakeholders,for subsystem platforms,the previous installed base is of importance;for system platforms,the diversity of the network of stakeholders is essential;and for evolved subsystem platforms,the judiciary is an important factor. Automation systems for buildings interconnect components and technologies from the information technology industry and the telecommunications industry. These industries, existing platforms and new platforms (that are designed to make building automation systems work) compete for market acceptance and back several platform battles among suppliers for building automation networking are being waged.It is unclear what the outcome of these battles will be and also which factors are important in achieving a platform dominance.Taking the fuzziness of decision makers’ judgments into account, a fuzzy multi-criteria decision-making methodology called the Fuzzy Analytic Hierarchy Process is applied to investigate the importance of such factors in platform battles for building automation networking. We present the relative importance of the factors for three types of platforms (subsystems platforms, system platforms, and evolved subsystem platforms). provide a first indication that the set of important factors differs per type of platform. For example, when focusing on other stakeholders, for subsystem platforms, the previous installed base is of importance; for system platforms, the diversity of the network of stakeholders is essential; and for evolved subsystem platforms , the judiciary is an important factor