The Transportation Worker Identification Credential (or TWIC) program is a Transportation Security Administration and U.S. Coast Guard initiative in the United States. The TWIC program provides a tamper-resistant biometric credential to maritime workers requiring unescorted access to secure areas of port facilities, outer continental shelf facilities, certain manufacturing facilities, and vessels regulated under the Maritime Transportation Security Act of 2002, or MTSA, and all U.S. Coast Guard credentialed merchant mariners. As of May 2014, there were 2,999,058 people enrolled in the program. Those seeking unescorted access to secure areas aboard affected vessels, and all Coast Guard credentialed merchant mariners, must obtain a TWIC. The new measures were fully implemented on April 15, 2