Client / Customer Relationship Management in the advertising, like many other businesses, starts much before the first interaction with the client and the never stops.
Advertising is and always has been a very customized service industry. Along with the different need and goals of every brand, agencies has to interact with different type of CEO, brand managers and their brand communications team. CRM thus sometimes have to me very customized too.
Brand consultancy firm sometimes get into situations where along with a bunch of small and medium level client there is one very big client paying a relatively much higher renumeration. In such situation generally a big team ( and sometimes every one in the agency in a smaller agency) is continuously dedicatedly working on keeping constant communication with the different people from client side, translating everything to the agency creative team and communicating feedbacks again to the clients.
There are though many standard procedures too which are followed to maintain a better customer relation and keep both the sides on the same page. I will be writing about some of them in some time.