Conflict in a work context has to be dealt with more delicately than with family, friends, dating, rest of the world, etc. People in the workplace anymore are toxic.
A few general practices I implement in my work life so I can keep my jobs and also keep my integrity (there is always tug-a-war between the two):
- Conduct as much business as possible in Email, text, IM, etc. Verbal conversations in a 2018 workplace are like walking on to a Civil War battle field in action with no weapons or armor. People have what's called "selective memory loss" which is exactly what it says.
- If you have to have a verbal conversation with anyone that's important, follow up with a 'per our conversation' Email.
- Demand a level playing field; for example, if this guy is talking to your client then you should demand the opportunity to do the same
- Never defame someone's personal character. In the case of your guy, if he is talking smack about you, tell your client "I must disagree with XYZ he said. The facts are ABC. I know he is busy and may not have intentionally told you XYZ, but that's plan flat not the case" (this is a politically correct way to call him out, even though what you really want to say may have a few harsh words. Again, you CAN'T use harsh words in a workplace safely in 2018. It's just too risky.
- If you confront someone about something, or they confront you, and you cannot otherwise agree, always propose to 'agree to disagree'. This goes a long way for me and I do it almost on a weekly basis.
- Always give your immediate boss a chance to help, but if they don't, then never be afraid to go over their head. A former police Sergeant of mine used to say "Everyone has a boss, I don't care who they are or think they are".
- Offense is always easier than defense. Handle problems proactively instead of reactively if you can.
Again, these are just some general things from someone who has swam in the toxic river of work place sludge far too much.
