The most common and respectful way to address someone with a PhD is to use "Dr." followed by their last name.
For example, if their name is John Smith, you would address them as "Dr. Smith".
There are some instances where you might use their full name, such as in formal written communication or when introducing them to others.
However, using "Dr." as a courtesy title is generally considered the most appropriate and respectful approach.
Keep in mind that not everyone with a PhD prefers to be addressed as "Dr.".
Some individuals may prefer to be addressed by their first name or by their professional title.
It's always a good idea to observe how they introduce themselves and use the title they prefer.
If you're unsure, you can always politely ask: "How would you like to be addressed?"
Using the appropriate title demonstrates respect and professionalism.
