There are about 4-6 people who interact with the client. Maria (Lead Project Manager) is in touch daily, but upper management as well as developers have some direct interaction too. All the work is translated at Jira, which is quite effective and helps to be transparent and open in communication.
With previous agencies, our client had a lot of temporary fixes. Our team, however, explains why things break, and that helps the problem not reoccur. Much of the work we've done enables the client to automate rather than rely on human effort.