So you have searched the national, state and even some county archives in your genealogical journey. You may have a birth certificate, a death record or even a pension record. But is this all that is available about a persons life?
There is possibility that more informational about the person in a private archives. Whether this was at a place the person worked for, school they attended or an organization that they were affiliated with. Finding these resources can be more difficult but many publish how to make inquires on their websites. Your relative many be part of a larger collection at the historical society or be in the archives of a large university.
This falls under the "leave no stone unturned" genealogy process.
I found out that a great great uncle of my mine was a Catholic priest. I had received a picture of him in a stack of pictures that got handed down from a relative that had recently died. Some of my older relatives were able to fill in a little about him like his name, but since he had no descendants, no one was really close to him. The most information that I found out was his name and that he was a a priest in Baltimore. That is not a lot of information, but it was something.
Doing research into the subject, I was able to find out that the Archdiocese of Baltimore being the oldest Catholic diocese in the United States maintains an archives at St. Mary's Seminary and University, the oldest Catholic seminary in the US. They have an extensive archives of the history of the Catholic church in Baltimore and early America. I send a query to the full time archivist at the address on their website.
I wasn't sure what if anything would be returned. Within a few weeks time I received a large envelope from the seminary. In it contained the "personnel record" for my relative which stated his ordination date and a list of every parish he had been assigned to from ordination until his retirement. It has information about his time at the seminary as well a copy of this ordination announcement. I was very surprised with my find.
None of this would have been known had I not looked further to a private archive. Many large corporations have achieves of employees as well as many churches. But if you limit yourself to only public archives you may be missing our on key elements of your family story.