[richem]

I try to take the stance that they simply forgot about the previous conversations or agreements. That generally has worked for me and keeps people from losing too much face which additionally helps keep everyone on the same side. Everyone forgets sometimes, sometimes its a genuine memory lapse and other times not so much. I've used variations of the following numerous times to decent result:

"Hi <so and so>, we talked about this matter last in <this email chain or that meeting>, I'm attaching the last <email/meeting summary>. If there's a need to readdress this <situation/decision>, please feel free to let me know and we can setup a meeting to further discuss."

That establishes what you consider to be the facts, based on whatever evidence you are attaching, and doesn't necessarily place you at odds with the client. You always need to figure out how to balance your client relationship with your project needs. Sometimes you may need to give a bit on the project needs to keep the client content but that is surprisingly less than most consultants think.

I've had several clients come back to me after an engagement has completed and mention that they were being intentionally difficult to see what else they could get but documentation helped prevent too much excess on my part. I've even been in the situation where I have acted as the client when dealing with vendor implementation teams and told specifically to be difficult to see what else we could get.

[RangerScience]

Interesting. Thanks for the insight and advice!

To reflect back what I'm seeing in your language use - to see if I've gotten the gist of it - your subtext / authoring attitude is "ah, you just forgot, let me simply re-inform" but you also don't bother mentioning any particular reason.