In one of our blog posts we presented a basic tool which extends the Openstack Nova client and supports executing API calls at some point in the future. Much has evolved since then: the tool is not just a wrapper around Openstack clients anymore and instead we rebuilt it in the context of the Openstack Mistral project which provides very nice workflow as service capabilities – this will be elaborated a bit more in a future blog post. During this process we came across a very interesting feature in Keystone which we were not aware of – Trusts. Trusts is a mechanism in Keystone which enables delegation of roles and even impersonation of users from a trustor to a trustee; it has many uses but is particularly useful in an Openstack administration context. In this blog post we will cover basic command line instructions to create and use trusts.