Dean? Are you sure you don't mean department chair? It's not clear from your profile whether you're in grad school or undergrad, but if you're a PhD student a

Dean? Are you sure you don't mean department chair? It's not clear from your profile whether you're in grad school or undergrad, but if you're a PhD student and the guy's really a dean seriously consider changing advisors even if he's a "big name"---it would be exceptional for a dean to be on the cutting edge of research, or to be spending as much time on research as you'll need. If you're an undergrad or master's student, no worries.