This article presents one writers position on the old question:
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You may've heard that "dots are used before things that Access names, and bangs are used before things that you name." Malarkey! It's just a coincidence that most of the things you name in Access end up in collections. Use bangs because they're being identified as members of a collection, not because you named them. FormName!ControlName is actually shorthand for FormName.Controls!ControlName -- the Controls collection can be left out because it is the default property of an Access form.#