Our normal Master Services Agreement (MSA) includes a clause that permits us to talk about our relationship with the client, and our work, in our marketing. Some clients are sensitive about this and ask us to run any posts by them before publishing. The ‣ should show the publicity requirements of each client.
We tend to only post about projects once they are live, but can showcase in-progress work if there is a specific reason. Get permission from the client first though.