5201 Auth Way
Camp Springs, MD 20746
Michael Sacco, President
David W. Heindel, Secretary-Treasurer
Chartered in 1938, the SIU is the largest North American union representing merchant mariners. The SIU is a federation of 12 autonomous unions, spanning the U.S., Canada, Puerto Rico, and Central and South America. Major employers of SIU members include: Maersk Line, Sealand, U.S. Military Sealift Command, and numerous other deep sea, Great Lakes, and inland operators.