PROMINENCE is a platform which allows users to exploit idle cloud resources for running scientific workloads with a simple batch system style interface. Key features include: - Jobs can be submitted from anywhere using any OS and any language. - All jobs are run in containers to ensure they will can run reliably anywhere and are reproducible. - Multi-node OpenMPI jobs can be run in addition to HTC jobs. - On-premises resources can be utilised with the ability to burst onto external clouds at times of peak demand. - Goes beyond bursting onto a single external cloud with hierarchical cloud bursting. For example, burst onto national research clouds, to EGI FedCloud and finally to public clouds. - All infrastructure provisioning is handled completely automatically and is totally transparent to the user. - Clouds are selected automatically based on job requirements and preferences, and any failures are handled automatically. - Output data can be accessed from cloud-based object storage.