Does the order in which you list committee members in a dissertation matter? I am currently writing my PhD dissertation and was wondering in what order I should list committee members in my dissertation? What is a good order that does not offend anyone? I know the advisor has to be listed first. For the rest of the members, some of the options I considered were: (a) listing by decreasing order of seniority, (b) alphabetical, (c) list external last. The problem with (a) is that the senior most professor is an external (from a different university) and comes up before Profs from my own department. The problem with (b) and (c) are that the senior most person, who is also quite famous, now comes last. Am I overthinking this?
Probably you are overthinking it. If they have different roles you can list them with their role and avoid ordering problems. Otherwise I'd consider alphabetical. 

I'll admit that in some fields there may be a tradition about how to do it, but I've never heard of that. And note that in some circles the one listed last is considered the most prominent. It is hard to really draw conclusions, hence alphabetical. 

And, your advisor might have some good advice about this.