How it makes you feel, what it does to your self-esteem and what it reveals about your fitness, health and age. You want to know how to conceal it or, if you're the confident type, how to act as though it's not even there.
It shouldn't cause us so much concern and, yes, we really should be able to rise above the whole silly issue, but the fact remains that upper arms (the displaying of them in public specifically) terrifies many of us.
The solution is a chic cover-up. Shrugs, for years the favourite of ladies who-go-to-fancy-balls, are OK but evening jackets are much better. Some of the best can be found on the high street.
Far left: Cropped sequined jacket, Jigsaw, £239. Call 0141 552 7639/0131 225 4501.
Left: Dress, NW3 at Hobbs, £99. Call 0207 586 5550.
Right: Satin shoes, Kurt Geiger London, £160. Call www.kurtgeiger.com.