managing toxic personalities in the workplace

something i hope I'll never have to deal with but inevitably will... The question is how well I'll be able to handle it. I know i'll be very quick to come to the conclusion that someone's toxic - I can read things like that easily and am almost too-decisive, but then what I do with that I don't know... In my personal life I simply cut them out - kill all ties with the individual regardless of the social costs. Done it before, would do it again. If someone hurts me or those I love they don't deserve a second chance. It makes for a healthier, more rewarding life in the end. But in a workplace things are completely different...