Appropriate dress?

It occurred to me today as I sat in a room full of clients and co-workers that dressing as a form of expression is a minefield at my age.

Right now I struggle with looking my age vs. looking "current" which my daughter is quick to point out at every opportunity. We both shop at Victoria's Secret but I am about functionality and she is about aesthetics. I don't understand why she can't wear anything more than a year or two when I have a closet full of many generations of clothing that is still perfectly wearable (by my standards). Each of us has a different definition of "vintage" as well.

Exposing one's mid-section may be OK at 30 but is it OK for me? Will my client find low rise jeans, Puma shoes and a t-shirt acceptable apparel for both of us? I feel good and comfortable but have no idea what is going throught the minds of my 20 and 30 year old co-workers. I've managed to get past bad hair cuts, too much makeup, and the 80s and 90s but have I gone far enough or am I one of those women that people look at and say to themselves, "she really should act her age."