IRIS OpenStack Cloud Services provide researchers with flexible, on-demand access to virtualised computing infrastructure that can be tailored to the needs of individual projects and scientific communities. Unlike traditional fixed computing environments, cloud services allow users to create and manage virtual machines, storage resources and research platforms that can be scaled to match changing requirements. The service supports a wide range of research activities, from software development and testing through to data analysis, scientific applications, web services and collaborative research platforms. By using the open-source OpenStack cloud framework, IRIS enables researchers to deploy consistent environments across multiple infrastructure providers, supporting interoperability, portability and efficient use of distributed resources. These capabilities complement traditional high-performance and high-throughput computing services, providing researchers with additional flexibility in how they undertake data-intensive and computational research.