Pros
Great benefits - on campus gym and workouts offered. Huge cafeteria - lots of selections. People are friendly and want to help. There are additional perks depending on your department. Because of it's size there are a lot of opportunities to advance - if you're willing to jump to different departments.
Kontras
For me - I had a HORRIBLE manager and when I tried to address the issues with upper management... nothing was done. Upper management was so afraid to lose the "knowledge" that this manager had, they looked the other way when terminable offenses were made. During my career I've found that the company as a whole can't really be judged based on one department. I know of other departments and managers in Alcon that provide some of the greatest environments all around - mentorship, progression, team building and just an overall ideal work environment. So while my personal experience had a LOT to be desired, I think there are enough departments in Alcon that would make it a great place to work and grow.