how to create the best team at work?

Many times, in small sized companies, I've found a negative behaviour from the employees. They are acting as enemies, comparing everything they are doing and trying to destruct or decreasse the work of their colleagues. I really think a transparent mentality is needed right now from all of us, from all the employees. The company's results depend on everybody, on each department, each phone call, each act. So, please just open your eyes and talk in the same direction and being concentrate on the main goal of the company and not the uggly tee-shirt of your colleague.
Just take a coffe together 5 minuts and talk about how you see how to improve