The most appropriate shoe to wear to your office is the one that draws the least amount of attention to your appearance. Because every office environment is different, the people you work with will have a set of unwritten rules about what is considered appropriate. A good general rule is, if people see your feet coming first, you've lost credibility.
CONSIDER THE CLIENTELE
If you work in a financial firm, as I do, then your shoes and clothing must send a message that you are a competent handler of client assets. If, on the other hand, you work in the front office of a boat-motor repair shop, as I once did, then 3" strappy heels will make walking through a maze of propellers to find the right hub for a "40 horse Merc" not only impractical but downright flirtatious.
MATCH YOUR SHOES TO YOUR DUTIES
Postal clerks stand all day, wait on customers, and sort mail. The wrong shoes can lead to chronic back pain and foot pain, not to mention irritability. The smart shoe for this job puts comfort before beauty. However, choose a pair of attractive, black flats with a good arch. Those neon-lime tennis shoes might make you appear frivolous and unsuitable for that promotion.
One of my friends gets by with wearing outlandish shoes to work. How? She works in the back office of a health club as a cardiac rehab specialist. Her main job is to cheer up and train recovering heart patients, which she does successfully with the help of her quirky shoes and coordinating outfits.
WHEN IN DOUBT, GO CLASSIC
The old adage is true: "Dress for success." You don't have to appear dowdy or behind the times, but certain styles are more appropriate for an office environment. For men, a brown or black casual lace-up is always appropriate - even if you work in the mail room. Save those old Birkenstocks for home. Beat up tennis shoes or boat shoes without socks sends a message to managers that you don't care - and that message is applied to your job performance as well as your appearance.
For women, flirty, flowing skirts and slappy slides may turn heads at a party after work, but turning heads is not your goal in the office. Choose a pointed-toe pump or slingback if you want to appear up to date, and soften that flirty skirt with a short blazer and shawl-collared blouse. Nothing ruins your chances for advancement like ultra-trendy clothing - or shoes from the "streetwalker" collection.
CONSIDER THE PURPOSE OF THE SHOE
Think about what the shoe is supposed to do, and keep it in its place. I love the feel of my Keen sandals, but they are meant for rugged outdoor activities and cannot be "dressed up" enough to pass office muster. That goes for men and women. My trendy, low-profile Nike running shoes are fun to wear with jeans at the mall, but they don't belong under my desk - on my feet. Those wedge lace-up espadrilles may look great at a beach party but they would do nothing for my professional image at work.
As you remember the purpose of a shoe, keep in mind the decade of the style. Retro may be the current rage, but if you wore it previously in your life and it is back in style, then you are too old to wear it again. Mary Jane flats might be cute on a 17 year old in tight stovepipe jeans, but they look ridiculous on a 40 year old administrative assistant or paralegal.
Invest in a couple of pairs of appropriate office shoes and keep them at work if you must. You can wear your comfortable casuals or trendy boots on the way to and from the office and at lunch, but take your job seriously enough to dress well and dress appropriately. Consider it an investment in your future.