Singapore Airlines is ranked the best among international carriers in the Best in Business Travel survey again this year, two years in a row.
For our second annual survey, Fortune partnered with Travel + Leisure to ask readers about their habits and brand preferences while traveling for work. They named their favorite airlines and rated them using a variety of criteria, including customer service, frequent flier programs, in-flight class experience, food and entertainment options, and airport lounges.
Here’s what sets Singapore Airlines apart from the rest:
• Many of its 15,000 menus are tailored to the carrier’s route map. First- and business-class fliers leaving from London, for example, can have a full English breakfast.
• KrisFlyer Spree, the airline’s new online mall, means passengers have nearly 2,000 brands—from Paul Smith to Muji—at their fingertips.
• A new premium economy class will debut on U.S. flights by the end of 2015, with custom leather seats, foldout leg rests, and 13.3-inch HD screens.
• A new customer-experience management system will soon give crew members access to passengers’ travel preferences.
See below for rankings of international airlines by survey categories.
Best International Airlines for Business Travel — Overall

1. Singapore Airlines
2. Emirates
3. Air New Zealand
4. Cathay Pacific
5. Qatar Airways
Best Customer Service

1. Singapore Airlines
2. Air New Zealand
3. Cathay Pacific
4. ANA/All Nippon Airways
5. Japan Airlines
Best Airport Lounges

1. Singapore Airlines
2. Qatar Airways
3. Emirates
4. Cathay Pacific
5. Virgin Atlantic Airways
Best Frequent-Flier Loyalty Programs

1. Singapore Airlines
2. EVA Air
3. Turkish Airlines
4. Cathay Pacific
5. Asiana Airlines
Best Economy Class In-Flight Experience

1. Singapore Airlines
2. Air New Zealand
3. Virgin Atlantic Airways
4. Japan Airlines
5. Emirates
Best Premium Economy In-Flight Experience

1. Singapore Airlines
2. Virgin Atlantic Airways
3. Air France
4. Lufthansa
5. British Airways
Best Business Class In-Flight Experience

1. Emirates
2. Singapore Airlines
3. Qatar Airways
4. Cathay Pacific
5. Virgin Atlantic Airways
Best First Class In-Flight Experience

1. Cathay Pacific
2. Emirates
3. Lufthansa
4. British Airways
5. KLM
For more on the Best in Business Travel 2015, visit travelandleisure.com/best-in-business-travel. To see the survey methodology, go here.
Read: Virgin America named the best U.S. airline for business travel