Pros
great culture, heritage; a lot of time is dedicated to teach the values and explain the vision; put in efforts to explain one's role and how you personally fit in the big picture; some trainings available; management stays relevant and communicates well downwards (via internal website, blogs, etc.) Great colleagues, a lot of colleagues to learn from; very nice bar. They are not quick to fire people (unless brutal violations of codes) they would try to bring out the best in you
Cons
Your career and days at an office can depend great deal on your immediate manager. I changed department and could not believe that I am still working for the same company. Perhaps it's not Diageo's fault, and even though mechanisms to speak up are in place, in practice they don't work perfectly, and oftentimes there is no point in trying to fight the mills, it's easier to just leave. depending on your immediate manager, fair to great amount of back-kissing should be in place in order to be recognized / promoted / rewarded. Post-crisis years came with deterioration of and cutting access to a great number of benefits, so those who've been with Diageo for years get more and more frustrated with the changing attitude, especially if one compares conditions between offices in London / Dublin and Budapest