SELECT DISTINCT with primary key?

[Mike Hildner]

MS SQL Server 2000:

I'm trying to get a list of distinct columns, but I also need the primary key. I thought something like this might work:

SELECT a.CmnPersonPK, b.LastName, b.FirstName, b.MiddleName, b.DOB FROM vCmnPerson a
INNER JOIN (SELECT CmnPersonPK, LastName, FirstName, MiddleName, DOB FROM vCmnPerson GROUP BY LastName, FirstName, MiddleName, DOB) AS b
ON a.CmnPersonPK = b.CmnPersonPK

but I get an error "Column 'vCmnPerson.CmnPersonPK' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause."

Been trying and searching, can't figure it out. How do I get a list where those four columns are distinct, but also retrieve the PK?

Thanks,
Mike