Pros
There is nothing good to say about Cognizant. Do not trust in the "good" comments that are on Glassdoor about this company, you can see they are totally fake, probably written by some manager of Cognizant to try to cover the real comments of their employees.
Cons
I had worked for Cognizant 1 year before I left the company for obvious reasons (In total 1.5 years as I worked with CPL half year before they took the ownership of the project). They made promises in a really fancy presentation at the Convention Center in Dublin. But that was it. I do not want to imagine how much money they spent in that show (they could have invested that money in their employees instead) to do nothing after. Well nothing, they cut the majority of the benefits that we had with the previous employers CPL/Manpower such as free cantine, flexibility, promotional processes, etc. It is sad cause the job was even fun surrounded of really nice people but they screwed it up. Firstly we gave them a chance but soon it was clear that nothing that they had promised was about to be true. New hires getting less salary for the exact same amount of job, or different depending on what you demand during the interview. The funniest part is that they order you not to talk about your salary with your colleagues, something that is basically impossible. They changed the whole contract in terms of time shift for some teams (working later and later every time), and in terms of productivity setting the targets 10% higher from one day to another. And they also have taken some people, who where mentors, back to basic operation duties, creating a horrible work environment. I wish all my friends working there get a better job soon. They deserve a company which cares more about them and not that much about the numbers. It is a pity but it is true. I imagine Cognizant promising Google a reduced budget to take over the project but I am sure Google is not aware of all the strategies they are implementing to reach that budget.