It's worth noting that:
* "Ming" is a nickname sometimes used for him, but it's not very common and might be considered informal or even disrespectful in certain contexts.
* "Lord Campbell of Pittenweem" is the title he holds after becoming a life peer in 2009, and he may be referred to this way in formal settings.
However, "Menzies Campbell" is the most common and respectful way to address him.