No Passing Zone
One of my clients repeatedly makes passes at my secretary when he comes into the office. I've tried lunch or dinner meetings instead, but there are certain materials that can only be accessed in the office. My secretary never complains, but she's visibly relieved when he leaves. How can I get him to back off without losing his business? And is it really worth it? I value my secretary more.
What a great boss you are!
Any time the client is invited to an appointment at your office, could you meet him and escort him in (essentially blocking him from interacting with your secretary)?
That way, if he makes a comment in front of you, you can apologize to your secretary immediately (Whoa, excuse him, Sally!) and then ask your client urgently "May I talk with you in my office?" then say, "Look, Fred, I really value our business relationship but I have to ask that you not interact with Sally that way. She is a respected member of our team and we would not want to make her uncomfortable. I really would appreciate that."
Then briskly move on. "Now, on to today's business at hand."
These visible efforts on your part should make your employee feel valued and protected and the offline discussion should give your client the hint. If he persists, fire the client.
Did it ever occur to you that this persistent lothario just likes to see your secretary and has boorish social skills? Indirect intervention is the best way to handle this, as you're not going to want to risk putting your client's nose out of joint, or embarassing your secretary.
When you know this particular client is scheduled, send your secretary on an "errand" out of the office or at least to another department, while that client is skulking around your office. If the client asks where she is, simply say "she's out." There is nothing much he can do to harass her when she's not there.