including contacts from different companies in same account

including contacts from different companies in same account

We deal with the company and their pr agency, but the pr agency represents more than one of our clients. Is there a way to keep track of the contacts via both the PR company and the individual client? Currently the only way we've found to do this is to have the pr agent assigned as a contact of that company. This doesn't help as when we talk to the pr agent, it's important to know which of her clients we're working with and on what projects. HELP!!