I assume that you want to pass the filter from the list box to the form that
you want to open, if that the case, on the DoubleClick event of the list box
you can write the code
Dim MyCondition As String
MyCondition = "[FieldNameInTableToFilter] = " & Me.[ListBoxName]
Docmd.OpenForm "FormName" , , ,MyCondition
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If the field you want to filter is a text type, then change the criteria to
MyCondition = "[FieldNameInTable] = '" & Me.[ListBoxName] & "'"
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