Alcohol can be a significant expense at your reception. Below is a list of options you have when it comes to serving alcohol:

Open bar

This is the most expensive option.  Your guests will be able to order any drink that they want and you foot the bill.  The bartender counts all the used bottles of liquor and charges you accordingly.  The problem with the open bar is that people tend to drink more than they usually do.  If you are worried about this, hire transportation for your guests. This will add to your expenses but it will also ease your mind.

Open bar during cocktail hour

This is an option that will help you save on alcohol costs.  Select a time (usually cocktail hour) and have an open bar during that time.  Once the cocktail hour is up, have a cash bar for the rest of the reception.

Limited bar

Another option to save you money.  Serve a selection of drinks (such as wine, beer and vodka drinks) during the reception.  All other drinks will be cash bar.

Well bar: this is an open bar with just "house" liquors being used - instead of the top brands.

Dry bar

If you or your family just don't drink alcohol, you can serve sparkling water, sodas and mixed nonalcoholic drinks.  It's OK not to serve alcohol at your wedding.  You could serve champagne to toast with if you like.