Hi Stephanie

I send out client feedback questions once in a while - haven't done so for a few months at least but mine is more a casual request for replies in certain areas of our relationship, the services provided, etc. I also use the opportunity to ask clients if they feel they're learning from us and if there's anything new they're interested in learning but haven't gotten into yet - we strongly believe in empowering our clients with knowledge (at least to the degree they wish to receive it

) and so this is an important part of the questions we send out.
Our clients are great about answering but to make it more fun for them we say 'for a change, we'll pay you!' and gift $X off the next invoice for every survey returned by X date.