A recent client, who has been receiving quite a bit of positive response from his new resume, had a great question about sending post-interview thank you letters. He wanted to know if he should thank everyone with whom he interviewed (including members of the sales team). He also wanted to know if it was appropriate to send both an email thank you and a physical thank you note. Despite some silly arguments to the contrary, sending post-interview thank you notes is a very smart idea. That includes a quick, targeted thank you to everyone with whom you interviewed. However, as I shared with this client, sending both an email thank you and a physical thank you note would likely be perceived as too much.
Remember, you are looking to show gratitude for interviewers' time (and to keep yourself top of mind during the selection process). You definitely don’t want to appear aggressive or desperate.