The little black dress is the ultimate night-out short dress. It's also a great base for a super-eye-catching coat. An LBD paired with a short faux-fur coat and pumps says "luxury." On the other hand, that same dress with a cropped leather or denim jacket, boots and lace or bright opaque tights has a youthful, rocker chic edge. Short coats may be able to keep a nighttime dress daytime-appropriate and can be checked at your destination when you want to transform into your nighttime look.
Short Dress, Long Coat
A long coat almost always lends a more mature style to any outfit. When layered over a short dress, however, the coat becomes the centerpiece of the outfit, and the dress disappears underneath it. Consider a bright or unusual color or interesting details like a houndstooth pattern or toggle closures to make your coat the focus of the outfit. Alternatively, a long trench can be a power piece that commands respect in the workplace and on the street.
Long Dress, Short Coat
Like a short coat with a short dress, a short coat with a long dress can be unexpected and fun. However, it can also be classic and understated. A major eye-catching piece like a fur coat will overshadow your dress, but keeping that piece smaller will showcase a longer dress, especially if the dress has long, detailed sleeves. Paired with a few skinny belts, a vest becomes a part of the outfit, not just outerwear. On the other hand, a coat with a blazer-like fit may look more professional with a long dress, especially if the coat reaches at least to the hip. This will give the office-appropriate impression of a skirt and blazer.
Long Dress, Long Coat
Layering on a coat that is longer than your dress is by far the most evening-appropriate and luxurious of all of the options. This pair appears richer due to the thickness of the dress and jacket pair. In this combination, the coat can take on an almost ball-gown like shape; this look depends on a dress that is slightly shorter than the coat. If the weather permits, consider keeping your coat open, and choose an expensive-looking texture or pattern to amp up this rich-looking style. For example, a military-style trench, especially with supple leather boots, works well. Rather than blending in with a solid, dark color, look for details in buttons and textures that will make you stand out.