Bob - Thanks for your help. I began with a three column format because month and day are sometimes missing for a given record.
I'm unsure how to design the query and where to enter the string you provided. I tried creating a select query from the table containing these fields and entering the string you provided as the "criteria" but ":" is an invalid character. I must admit, I'm a novice when it comes to Access so please forgive my lack of experience.
Bob - Thanks again. The first option (display in query) worked like a dream. Also wanted to try the second option. Do I enter this command in the field area too? And will this create a new field with the converted date? or will it convert the 3-column format to a single column? I need to keep the existing 3-column format for other applications.