The basics of an invitation suite are pretty clear-cut: You include the invitation most likely with a response card. But there are plenty of other inserts that may be useful for your celebration. Whether it's a separate reception card or an admission cards, here are some of the additional pieces of stationery you may want to include with your wedding invitation.
What is included in your wedding's invitation suite all depends on the type of wedding you're having. If the whole shebang will go down in one location, you're invitation will likely be minimal with a response card and possibly directions to the venue. But, sometimes, added notes are needed. Let's say your ceremony will be held at a sought-after cathedral in a big city that attracts tourists. In this case, you may want to include an admission card to heighten security and privacy. In a similar vein, if you're holding a large ceremony and wish to reserve pews for close family and friends you may include pew cards with the number pew they're supposed to sit in engraved or written on it. This way, you'll ensure that your mom, dad, close cousins, and best friends will get the seat that you wish them to have.
Some other additional notes could be an at home card, which provides invitees with your new address if you recently moved. You can (and should) include a map and directions to your wedding's venue, especially if your reception site is different from your ceremony site. Last but certainly not least there's a rain card for if you're planning an outdoor ceremony. This card include the in case of emergency indoor location you've chosen due to the potential of inclement weather.