Appropriate attire for a graduate school interview in the US I was invited to interview at several graduate schools this upcoming February. All of the programs are in the fields of biochemistry and biophysics. What is appropriate attire for graduate school interviews? One of the schools mentioned business casual. Does anyone have any good suggestions? I thought about wearing a sweater with an oxford underneath. However, I will also bring a sport coat just in case.
In general, you want to look neat enough to make it clear that you are taking things seriously, but not so formal that you give the impression that you are overly formal or don't understand the norms.  Typically slightly overdressed is better than slightly underdressed.  Your goal is to have people not particularly notice what you are wearing, and instead listen to what's coming out of your mouth.

Standards vary slightly from field to field: in my experience, mathematicians tend to be the most informal and chemists the most formal of the STEM world (business students and liberal arts exist in their own separate universes, which I am less familiar with).  

In general, however, I would suggest that men wear a sharp-looking long-sleeved button-down shirt, long pants, no jacket or tie.  For women, the rules are more complex (and I am less familiar, but am incorporating advice shared from experiences of female scientists who I know), but something at that same level of "business casual" is probably good; long-sleeve button down, or a sweater; avoid cleavage or anything that can be taken as sexy.  Unfair though it may be, pants are probably better than even a long skirt or dress for that reason.  Heels can help for height, but don't wear sharp heels or heels that make noise. Low to no makeup, as there is often prejudice against that (again, not claiming any of this is fair). 
Make sure your hair is clean and presentable too; if you have long hair, you will probably want to tie it back (men and women both).

Contrary to all this: if you have a strong sense of style and good personal visual taste, you can probably make all manner of things work.  But make sure you're confident you can pull it off---if you can, you probably already know it.  For the rest of us, I just recommend making the clothing unmemorable.