I am about to go on a two-day trip to interview with an out-of-town employer. The first day, I will have dinner with the third-party recruiter. The second day, I have an interview at the company's facility, from noon to 3 p.m. I board my return flight at about 8 in the evening.
My question is: May I properly schedule other meetings while I'm in town? I have two college friends I would like to check in with, and a professional acquaintance had asked that I check in with him the next time I'm in town. Am I expected to reserve all of my time for the employer who brought me there, or may I make my own arrangements for my unbooked hours?
You need to be clear with the employer about when you'll be available and when you won't, and they should be clear with you about when they need you. Since you've reserved the time that was requested of you—dinner with the recruiter and for the site visit the next day—it's perfectly fine to make other plans. However, it's a good idea to let the search person know that other blocks of time will be spoken for, in case there's the chance the employer would like to schedule additional interviews for you. Make sure there are no surprises.
What you can't ethically do, in my opinion, is travel on someone else's dime and seek out other job interviews. Now, you might wonder what happens if, let's say, you call the acquaintance who asked you to look him up on your next visit and he says: "I'd love to have dinner and bring my friend Carol with me, because she's looking to hire someone like you right now."
Suddenly, your casual dinner begins to sound like a potential job interview. But I don't think it would be bad form to have that dinner, because it wouldn't be about your having sought out such an opportunity.
Bottom line: You do owe the headhunter and his or her client as much time as they request, you shouldn't seek out other employment opportunities, and you're on your own socially. If a pal happens to bring along someone who might be helpful to you professionally, that's a bonus.