Yes, Estonia can issue both single-entry and multiple-entry Schengen visas. A multiple-entry visa allows the holder to enter and exit the Schengen Area more than once during the visa's validity, provided the total stay does not exceed 90 days within any 180-day period. Whether a single or multiple-entry visa is granted depends on the applicant's travel history, the stated purpose of the visit, and the decision of the issuing authority. A multiple-entry visa is particularly useful for those planning visits to multiple Schengen countries or anticipating return trips within a short period.