On Tue, 17 Oct 2006 17:25:02 -0700, NetworkTrade
wrote:

Obviously they must share the same field ID...so neither/either is
inherently primary per se...in ones mind the table that is used most
frequently I tend to think of as the primary....

Well, as implemented in Access (and SQL/Server, Oracle, MySQL, and
others), you're mistaken; even one to one relationships have
directionality. If you are going to enforce referential integrity,
there must be a record in the "primary" or "left hand" table, and
there may or may not be a record in the child table. Strictly
speaking, it's a "One to (Zero or one)" relationship.

John W. Vinson[MVP]