An environment is a user-defined collection of resources that host an application. Environments are typically modeled on some stage of the software project life cycle, such as development, QA, or production. A resource is a deployment target, such as a database or J2EE container. Resources are usually found on the same host where the agent that manages them is located. A host can be a physical machine, virtual machine, or be cloud-based.

Environments can have different topologies–for example: an environment can consist of a single machine; be spread over several machines; or spread over clusters of machines. Environments are application scoped. Although multi-tenant machines can be the target of multiple applications, experience has shown that most IT organizations use application-specific environments. Additionally, approvals are generally scoped to environments.

Serena Release Automation maintains an inventory of every artifact deployed to each environment and tracks the differences between them.