The prime purpose of the invitation is to impart critical information about your shower to the people you want to come. Even if the party is a surprise to the mother-to-be, do not try to surprise the guests. The invitation should also convey the spirit of the shower. A whimsical phrase or quote or a clever turn of phrase that incorporates your theme helps to set the tone for the happy time to come.

People want and need to know what to expect—whether it’s dinner or lunch or a snack—what to bring, what to wear, how fancy or casual the party will be, and any other particulars that will affect the guests. It’s the hostess’s job to prepare the guests for the event, and it’s the invitation’s job to deliver that information.

Here’s what every invitation should include:

• Date, time, and length of the shower (i.e., when you want them to arrive and leave)

• Who is included in the invitation (kids, dogs, spouses or mates)

• The name of the mother-to-be and the baby’s name and/or gender if known in advance.

• A map to your house or the location (if specific information is needed to get there)

• Gift information (the registry, themed gift ideas like the layette shower, etc.)

• Meal to be included (If you are serving a meal, mention dinner and drinks, a luncheon, a brunch, cocktails and appetizers, etc.)

• What to wear, if necessary (e.g., “Everyone should wear something pink,” or “swimsuits and jeans,” etc.)

• R.S.V.P. information—such as a phone number or e-mail address (essential if you need a food count)

• A deadline to respond to the R.S.V.P.