Great question Kathy! Currently there isn't a way to notify when a client has viewed an invoice. This is a feedback request we've received before and we do have an open request for it in our feedback center. We have added you to it which counts as a vote in it's favor and ensures you are notified if it is added to our roadmap.

If any other Thryv users would also like to be added or have an idea to share, leave a comment below!