Which document is essential for verifying a Sailor's service history before making a request for special designation?

The Electronic Service Record (ESR) is essential for verifying a Sailor's service history before making a request for special designation because it provides a comprehensive and accurate digital account of a Sailor's entire military career. The ESR contains detailed information, including periods of service, assignments, qualifications, training, awards, and other critical service data. This centralized digitized record helps ensure that any evaluation or request for special designation is based on the most current and validated information available.

In contrast, while a Service Record Book may contain some of the necessary information, it is typically a physical document that might not be up to date or as comprehensive as the ESR. A Personal Data Sheet may offer basic personal details but lacks the depth and breadth of service history needed for such evaluations. The Military Service Agreement outlines a Sailor's obligations but does not provide operational or career history, making it unsuitable for this purpose. Therefore, the ESR is the primary and reliable source for verifying a Sailor's complete service record.