Semi-casual is an American dress code which accommodates options beyond traditional slacks in the workplace. Semi-casual is a step below business casual.
The regulations for semi-casual dress are varied from location to location. One of the defining variables for semi-casual appropriateness is climate. Blazers and sport coats, cashmere crew neck or v-neck sweaters, thin turtleneck sweaters and patterned slacks are all appropriate in a semi-casual context. GQ recommends gray flannel slacks as an example of a semi-casual piece.
Regulations for suits are different in the case of semi-casual. While a business environment requires dark-colored suits, semi-casual wear can be lightly colored. Women can include skirts into their attire. Semi-casual does not require a suit, however, and wearing a business suit in a semi-casual environment would be overdressing. Semi-casual attire does not require that one wears a tie.
Depending on the line an office decides to draw, high-quality jeans and tennis shoes are sometimes acceptable alongside a dress shirt, polo shirt or high-quality sweater. Luxurious materials typically make casual pieces more appropriate in a semi-casual context.
Semi-casual dress is appropriate for career fairs, dropping off resumes and applications and certain office settings. Semi-casual is a good option for those who may be attending a non-work related reception or party where they might encounter someone involved in their hiring process.