Do you mean moral integrity?
Depends on where you work, really.
Of course being friendly and upright and honest in your contacts with co-workers and superiors and fulfilling the terms of your work contract as well as you are able to is applicable in any work place.
But some people can do more, depending on their position. If you are in no position to decide that, you can still make proposals.
You might find ways to help financially weak co-workers with organizing things that help them. Like, for example if many of them use public transports, you'll find that some public transports companies will give better prizes if your company buys 100 annual tickets and sells them to their staff.
You could encourage your company to advertise by sponsoring charity organizations.
You could encourage your company to hire and teach trainees.
If you witness anything that is going wrong in your workplace - whether it's people bullying a co worker, whether it is people making immoral bargains for the company or people making immoral bargains on expense of the company - you should inform people who will help you evaluate the situation (your boss, your bosses boss, anyone) and see that measures are taken to stop immoral behavior.
Integrity is largely impossible, especially in modern society. Nobody's actions can ever live up to their ideals and when faced with competing tests we have to make our choice which is more important and compromise on the other. I'm reminded of when Ayn Rand was caught lying about her academic achievements. Honesty was one of the highest priorities in her philosophy's ethics but attracting followers was a competing demand. If a lie could convince more people to be truthful doesn't the lie in effect cause the world as a whole to be more honest? I have personal needs I have to sometimes ignore; sometimes I have to be less of a husband than my wife deserves and sometimes I have to give my job less than the effort I promised when I took the job. One can only muster so much time and energy to meet all of our obligations so all of us are constantly weighing the importance of every obligation. Considering our promises to ourselves, our families, society at large, and our employers everyone is forced to be a hypocrite in one area or another most of the time.