Alex said:
Thanks for your response - given your caution, what is the best way
then to have a field that will increment by one for each records?
Usually in the form used for insertions you use code to assign the number.
The simplest version of this is to use DMax() to determine the highest
existing value and then add 1 to that. As long as you don't have a lot of
users simultaneously entering records doing this in the BeforeUpdate event
of the form works the best.
If Me.NewRecord Then
Me!IDFieldName = Nz(DMax("IDFieldName", "TableName"), 0) + 1
End If