Costumes écossais

Three piece, if you are buying one. The waistcoat lets you take the jacket off at a reception without the outfit collapsing, which on a long day matters more than it sounds. It also means you own a tartan waistcoat you can wear separately with a plain jacket, which effectively gives you two outfits.

As a guest at a relaxed or creative wedding, yes, and it will be the best dressed thing in the room. As a guest at a formal wedding, no, because you will out-pattern the wedding party. As the groom it is a bold and legitimate choice, provided the party is coordinated around it rather than competing with it.

Something quieter than you would choose for a jacket alone, because the sett now covers the whole body. Weathered, hunting, charcoal and grey based colourways carry across a full suit without overwhelming. Strong reds and bright modern colourways work only where being looked at is the intention.

White shirt, solid tie, one tone of shoe. Nothing else patterned anywhere, including the pocket square and the socks. The suit is doing all the work and every additional pattern subtracts from it. If you want a second tartan element, a plain pocket square in a colour from the sett is as far as it should go.

Batch variation. Tartan is woven in runs and slight shade differences between them are normal. On a single garment nobody would ever notice. With a jacket and trousers of the same sett standing next to each other, it reads immediately as mismatched. One order means one cutting run from one length of cloth.

Premium acrylic woven to the sett, which holds a pressed crease through a long day and resists the shine that heavier cloth develops at the seat and elbow. Have it professionally cleaned rarely rather than often, hang it immediately after wearing, and press through a cloth on a cool setting.