Managed lifecycle roles are disclosed. Managed lifecycle roles may be used for secure credential vending or otherwise. For instance, an entity (e.g., administrator or other entity) requests, via an interface of a role manager, creation of a role associated with a lifecycle definition (e.g., an expression of an enforceable expiration of the role or similar characteristic). The role manager stores the role and role lifecycle definition to a data store. Another entity requests to use the role to perform some operation with respect to a resource. A credential service validates the request against a lifecycle definition for the role (and against an access control list, in some examples) and responds to valid requests with credentials useable to perform the operation with respect to the resource. The other entity uses the credentials to perform the operation with respect to the resource. A sweep process manages attributes of the roles.