I have been trying by best to create a definition query which would select a group of municipalities from among the many in my state. I have tried commands of all sorts of variations from "Name"='Chatham'AND 'Chester' AND 'Far Hills'..... to "Name"=('Chatham', 'Chester', 'Far Hills... and so on but I keep getting an error when I try to validate.
Building a query expression. Check the Combining Expressions sub-heading to see how to use the AND/OR operators correctly.
For your example you should implement "IN":
"Name" IN ('Chatham','Chester')