With the Internet of Things (IoT) evolving more and more, companies active within this area face new challenges for their Identity and Access Management (IAM). Namely, general security, resource constraint devices, interoperability, and scalability cannot be addressed anymore with traditional measures. Blockchain technology, however, may act as an enabler to overcome those challenges. In this paper, general application areas for blockchain in IAM are described based on recent research work. On this basis, it is discussed how blockchain can address IAM challenges presented by IoT. Finally, a corporate scenario utilizing blockchain-based IAM for IoT is outlined to assess the applicability in practice. The paper shows that private blockchains can be leveraged to design tamper-proof IAM functionality while maintaining scalability regarding the number of clients and transactions. This could be useful for enterprises to prevent single-point-of-failures as well as to enable transparent and secure auditing & monitoring of security-relevant events.