People will want to congratulate you on your engagement, and let's be real: A party's a lot more fun than a phone call! It's also a great time to introduce key people from your lives who are going to be seeing a lot of each other (and possibly helping plan your wedding together) over the next year or so. "It's the first time you’ll have different groups of friends and generations really getting to know each other in a more intimate way," says celebrity wedding planner Jung Lee of Fête NY.