What if you bring your own bottle? Well, first, call ahead and see if it’s even possible. Some places do not allow it; others discourage it with a hefty “corkage fee,” a charge (typically around $15, though it ranges wildly) for bringing your own instead of ordering off the restaurant’s wine list.

That corkage fee makes business sense. After all, a restaurant makes a hefty portion of its profit (not to mention covers glassware and service costs) on alcohol sales so that food costs can be kept in line. If diners bring their own wine, they are cheating that system.

A good wine list is also part of the whole dining experience, and the diner who brings his own bottle is missing out on that part of the experience. The restaurant (hopefully) is proud of its wine list, and wants to share its finds with you; bringing a bottle takes away that opportunity.

If you do have a special bottle or bottles you’d like to bring, let the restaurant know what they are; if the wines are special enough, they may give you a deal on the corkage fee. (For example, say you wanted to open up an array of Romanee-Conti Burgundies from 1945 and have some of the chefs fine food to accompany it. That might be justification for some leniency.) Either way, though, remember to tip as if you had purchased full bottles of wine. Your bill may not be as high, but the staff worked just as hard.

The range of sommeliers is so wide in talent and experience and the array of pay scales that restaurants use are so huge that there’s no clear answer to the question of whether to tip the sommelier. Generally, if the sommelier went out of his way to accommodate you (like found some special bottle of wine for someone’s birthday, or decanted old wines you brought in from home), then do offer a tip.

If you’ve brought wines, do add the cost of the bottles to the final bill and tip on that total; each one of those bottles did add work for dining room staff and dishwashers alike.

Otherwise, it’s up to you, but my advice is not to feel obliged to tip the sommelier separately from the staff unless he’s gone out of his way for you. A nice alternative gesture, when you’ve brought or ordered a special bottle, is to save a glass for the sommelier or the kitchen. It’s not like most restaurant workers can afford to open such bottles that often for themselves.