The most convenient option is to fly directly into the South Bend Regional Airport (SBN). SBN is served by several airlines: Delta through Cincinnati, Northwest through Detroit or Minneapolis, Continental through Cleveland, United through Chicago O'Hare (ORD). Air service is also available with AllegiantAir to/from Indianapolis, also an international airport. SBN is about seven miles from Notre Dame with taxi service (about $13--15), hotel shuttles, and car rentals available. A less expensive but still reasonably convenient option is to fly into Chicago O'Hare (ORD) or Midway (MDW) and take CoachUSA service to Notre Dame. (See next.)
There is express bus service, CoachUSA, from both Chicago O'Hare and Chicago Midway every day at 2 hour intervals from 6:50 a.m. to 8:50 p.m. This especially makes Midway a good alternative because several additional airlines including Southwest are available there. Coaches are clean, modern, and comfortable and make only 1 or 2 stops in northwestern Indiana, the trip taking about 2.5 hours. One-way cost is $36; round trip $63. Drop-off points at the airport or the Morris Inn at Notre Dame.
If you rent a car, driving from Chicago is 2.0+ hours depending on starting point, city traffic, time of day, construction, and your nerves. O'Hare is on the NW side and requires driving through the city (inner or outer freeways, tollways). Midway is west of the Loop and therefore closer, eliminating the northern tier of freeway driving. Chicago is notorious for having freeways under construction and repair all of the time and, of course, rush hour driving is only for the calmest! Count on 2.5 hours if driving from O'Hare plus time for the unexpected, which is to be expected.
There is also a daily commuter train, the South Shore, with 5 runs between downtown Chicago and South Bend. Both Chicago airports are accessible to the Loop via metro trains and the metro trains stop near the South Shore terminal in the Loop. The South Shore is a nice option if attendees would like to spend some time in downtown Chicago before or after the conference ($10.75 fare each way). South Shore terminal is located at the South Bend Regional Airport so Transpo ($.75) or taxi ($13--15) is necessary to and from Notre Dame.
Amtrak service is available into South Bend along the New York/Chicago corridor. The Amtrak station is just a couple of miles from UND by taxi ($8).
The University of Notre Dame is immediate to an exit of the Northern Indiana Toll Road (exit 77) so it is easy to find by auto travelers from east and west. Highway US 31, a four-lane, leads to South Bend from points south, connecting with Interstate 70 at Indianapolis. Travelers driving in from anywhere in the Midwest will find easy access to the Toll Road via Interstates 65 and 69 in Indiana, 55 in Illinois and 75 in Ohio. Interstate 94 also comes into Indiana from the west as far as Michigan City where the driver should exit on US 20 to South Bend.
City bus service (South Bend Transpo) operates routes on the hour and half hour with stops at ND and the airport and at points downtown and the shopping areas/malls. Fare is 75 cents. Transpo is a convenient option for dining in downtown South Bend in the evenings. While downtown, hop on the Trolley for 25 cents and you can get anywhere in the downtown area.