A communications arrangement is implemented for tag-field type communications signaling. According to an example embodiment of the present invention, a communications arrangement, such as a PCI Express type arrangement, is configurable for communicating over a communications link using a tag (or similar) available field. According to an example embodiment of the present invention involving PCI Express communications, a first PCI Express endpoint device (150) is adapted to communicate selected information (e.g., synchronous event signals) to a second PCI Express endpoint device (152) using the tag field of data posted to a PCI Express communications link (130). The tag field is set to indicate a characteristic of the synchronous event, and passed from the first PCI Express endpoint device to the second PCI Express endpoint device.