In these economically challenging times, it's perhaps inevitable that some agency/client relationships will become strained. I remembered the old words of advice for dealing with tricky situations. These have been around so long that they may be new to younger readers:

When the client moans and sighs
Make his logo twice the size
If the client still proves refractory
Show a picture of the factory
Only in the gravest cases
Should you show the clients' faces

Kevin Chesters supplied a few additional verses for the modern age:

If the ads have gone to pot
Mention blogging quite a lot

If you want to dazzle them
Drop in terms like CRM

To make your clients think you're sage
Give campaigns a myspace page

To make them think you're clever chaps
Make references to Google Maps

If accused of strategic shirking
Bang on about social networking

If they still think the work is crap

You must present an iPhone app