Black & White Ball Appropriate Attire

Dear Dr. Dave and Dr. Dee,

When invited to a Black & White Ball, what should one wear? Does this title indicate what to wear, formal or semi-formal? If formal, do men wear black tie and women white gowns?

Signed,

Formal or not?

Dear Formal or not,

A Black and White Ball usually indicates formal attire. Men dress in black tie and women can wear black or white dresses.

However, if the invitation does not indicate appropriate attire or a particular theme, then it would be fine to ask the host.