Your big day is one of love and bliss, but most weddings also come with a hefty dollop of tense exchanges and awkward moments -- a sibling scuffle, an unenthusiastic bridesmaid, a delicate discussion about who's paying for what. Defusing these conflicts with grace is a must. 

After all, "a wedding is a precedent-setting event, and the choices you make set the tone for future relationships," says Anna Post, an etiquette expert at the Emily Post Institute. Here, she and other manners mavens share solutions to 14 common wedding-related dilemmas and tell you how to keep your cool when things get heated.

Dilemmas and Solutions
1. Fashion is not your mom's strong suit. You're worried she'll show up at the wedding wearing something tacky or inappropriate.
Seek the help of a third party. "Ask her to join you for an afternoon of shopping, and use a personal shopper or sales consultant to take the pressure off," says Karen Bussen, author of "Simple Stunning Wedding Etiquette" (Stewart, Tabori & Chang; 2008). 

She'll be more likely to accept fashion advice from a professional. If she still ends up picking something completely hideous, keep your disappointment to yourself: "In the end, a happy mother, wearing what makes her feel great, is much more important than a perfect photo opportunity," says Bussen.

2. His parents aren't contributing financially, but his mother still insists on having a say in the wedding planning.
Head her off by asking for her help in small, specific ways -- such as deciding on the seating arrangements for her family's tables or designing a groom's cake with her son, suggests Elise Mac Adam, author of "Something New: Wedding Etiquette for Rule Breakers, Traditionalists, and Everyone in Between" (Simon Spotlight Entertainment; 2008). "If you didn't plan on a groom's cake, this might be the moment to consider it," notes Mac Adam. And remember, if your future in-laws are hosting the rehearsal dinner, your mother-in-law automatically gets as much control over it as she wants.

3. Your parents are paying for the wedding, but they want a very different event than what you and your fiance envision.
First, express your gratitude. Then, explain your preferences in a non-defensive way. "If you emphasize how pleased you are, it will be easier for people to see why you like the things you do," says Mac Adam. Then try to compromise. If you want 40 guests and they want 150, pick a number in between. If you're set on a simple wedding and they want something more elaborate, Mac Adam suggests giving your parents free rein over some creative elements, such as the invitations. 

If the list is loaded with so many of their invitees that there's little room for yours, offer to contribute some of your own money in order to include more of your friends. If all else fails, though, you'll need to let them do it their way, unfortunately -- or foot the bill yourselves.

4. You're not keen on asking your fiance's sister to be a bridesmaid. You barely know her.
"You don't have to ask her, but for the sake of family harmony it's best to make every effort to include his siblings," says Sharon Naylor, author of "The Bride's Diplomacy Guide" (Adams Media; 2007). "Don't think about now. Think about the future -- when you're at his family's Thanksgiving, and you and his sisters have great wedding memories to share." The one exception: If the sibling -- either yours or his -- strongly and vocally disapproves of your union, you may, without guilt, leave her out.

5. You and your husband-to-be are vegetarians. Your families are decidedly not.
Whether you avoid animal products, alcohol, carbs, or anything else, "your wedding is not the time to try to convert people to your way of living," says Mac Adam. The trick is to be true to your beliefs without making guests feel deprived. For example, rather than serving seitan, tofu, or other unfamiliar foods, consider a non-meat pasta. Or offer a choice of vegetarian and non-vegetarian entrees. 

Mac Adam recalls one bride whose parents wanted to serve a kosher meal, although only a handful of guests required it. The bride hired a second, kosher caterer to prepare that food. "There is usually some sort of middle ground," Mac Adam says.