There are several types of papal audiences. This page deals with the general audiences, as they are the ones that are easiest to get access to. The general audience takes place on Wednesday mornings. In addition to these, there are other ceremonies and Masses celebrated by the Holy Father that are open to the public.
To take part in the general audience, it is necessary to reserve tickets. They are free, and are distributed from the Prefecture of the Pontifical House (Prefettura della Casa Pontificia) in the Vatican City, entered through the Bronze Door in the right-hand (facing the basilica) collonnade. The office is open on weekdays from 9 a.m. to 1 p.m., and the phone number is (+39) 06 69 88 31 14. Tickets should be reserved several days in advance. You can also try faxing them on (+39) 06 69 88 58 63. Please note that opening hours and telephone numbers may change. The fax will need to contain contain information about the number of persons you need tickets for, the date you're interested in and your contact address in Rome. No matter how you book tickets, they must be collected at the Bronze Door as mentioned above. An alternative is to ask your hotel to provide tickets; many hotels will do this.
The procedure for acquiring tickets for Papal Masses is the same as for the general audiences, but it is slightly more difficult as there are far fewer tickets available.
You should be at Piazza San Pietro at least 30 minutes before the audience, as there are a lot of people trying to get to their seats. There may be security checks, including metal detectors and x-ray checks of handbags.
If it's hot, it is a good idea to bring some drinking water. If you feel ill, from heat or any medical problems, alert the staff. The medical staff is very efficient and competent, so you'll be in good hands.
Wheelchair users should inform the Prefecture when they reserve tickets so that the necessary assistance is provided. It is not uncommon that those in wheelchairs are allowed to site very close to the Holy Father and even to approach him for an individual blessing. The alternative, trying to get through the crowds, might be impossible. Disabled persons not using a wheelchair might also want to inform the Prefecture of their condition, as it might be possible to borrow a wheelchair; the distance one might have to walk and the crowds pushing can make it impossible to attend in any other way.