Our services


We provide training and have access to towing vessels and designated examiners that can help you with your advancement to Mate (Pilot) of Towing or Master of Towing. Since 2009, we have helped many mariners by providing a platform to complete both the maneuvering requirements as well as discussion based assessments in the Towing Officer Assessment Record. Our program utilizes a working tug and barge with a full crew in the presence of a USCG approved designated examiner.


Diamond Marine Services has made it even easier to submit your original, raise-in-grade, or renewal applications. We will work with you to ensure you have all the proper paperwork in place to achieve your renewal or raise-in-grade without experiencing delays with the National Maritime Center and USCG REC offices.

USCG Approved Courses

We are pleased to provide a suite of ONLINE USCG Approved Courses in partnership with US Captain's Training. You will be able to study at your own pace from the comfort of your own home or from work. When you are ready to test, USCT makes it easy with USCG Approved ONLINE final exams! Courses include Apprentice Mate Steersman, OUPV Original Issue, 100 GRT Master, 200 GRT Upgrade, AB and many others!


Our program is reserved for experienced mariners. Mariners holding an OICNW endorsed license (STCW II/1 or II/3) can complete all the assessments in the TOAR with our program. If you do not hold an OICNW endorsement, you may be able to join us but we may not be able to complete the TOAR in its entirety. In addition, the extra sea service needed to upgrade to a mate or master of towing from a lower level license is often a surprise to many. For these reasons, we request to open a line of communication so we can better assess your needs. Mariners holding licenses LESS THAN 500 GRT (master or mate) or those without an OICNW endorsement are accepted on a case by case basis. For more information about this, please feel free to email or call us. 

Do you also need the observation sea service?

We are pleased to be able to offer those who need 30 days of training and observation a platform by which to accumulate the required sea service. This service is available to any mariner that already holds a completed TOAR (does NOT have to be from our program). For more information, please visit out TOAR page or call us at 877-335-6341 to see if this better fits your needs.


Time Date Seats
8:30 am - 4:00 pm Dec 7, 2021
Boston MA
There are 4 seats available.
8:30 am - 4:00 pm Dec 16, 2021
Boston MA
There are 1 seats available.

Credential Consulting

Tired of sifting through CFRs and NMC checklists wondering if you have enough sea time or completed the necessary requirements for an upgrade? Have you experienced delays or even have a license expire due to an issue with a previous application? Diamond Marine Services offers a unique service with former National Maritime Center evaluators on our credential consulting team. We have created a full service solution to help with all USCG credential applications.


Fully ONLINE courses in cooperation with


From OUPV and AB all the way to Master 200 GRT and Apprentice Mate, US Captain’s Training has courses that allow you to study and complete all exams without ever stepping foot into a brick and mortar classroom.
Save on travel expenses and study at your own pace!
Rated 5 out of 5
5 out of 5 stars (based on 104 reviews)
Very good0%

Check out our most recent reviews. 

Please see our REVIEWS page for more!

Great Experience

Rated 5 out of 5
November 19, 2021

Sam and his team were very courteous, knowledgeable and efficient. I took the inland TOAR in Boston Harbor and learned a great deal in vessel and tow maneuvers with Ben and Caitlin. Everyone was very skilled and friendly. I also had their credentialing service advise me in getting my application into the USCG whilst also applying for a license I didn’t know I was eligible for. They can save you a lot of time and money as opposed to figuring this out by yourself.

Mark Paterson


Rated 5 out of 5
November 17, 2021

Sam went above and beyond to help me get all of my paperwork filled out appropriately to obtain my 100 Ton license. The whole process went so smoothly and he answered every question I had. Thanks to diamond marine I am now holding my credential less than 3 weeks after my application was submitted. This service is worth its weight in gold! I look forward to working with them again in the future and would highly recommend them for anyone!

Blake Applewhite

Professional, knowledgeable and efficient!

Rated 5 out of 5
November 9, 2021

Sam’s knowledge and experience pays dividends with his fast and efficient service! He thoroughly prepared and submitted my MMC renewal, and despite the delayed processing times stated on the NMC’s website, he managed to get my MMC renewed and back in hand in less than a month! Sam and his team are amazing and I highly recommend them for all your licensing needs!

Dennis Amador

Sam pulled it off with 3 days to spare before expiration...!

Rated 5 out of 5
November 8, 2021

Sam is the best…! The organization behind Sam is the best…! I was amazed at how Sam turned around my complicated renewal and upgrade in less than 3 weeks. I highly recommend this for every aspiring Captain or renewal Captain wanting to present themselves professionally for consideration to the USCG. Your time is valuable and the normal process has become just too complicated and prone to delays. If you want effective and efficient turn around for your documents, Sam is your man…!!! ,

Keith R Clark

Excellent very easy and no problems everything was handled

Rated 5 out of 5
November 4, 2021

This is worth every penny I would highly recommend it. They walk you through every detail and make it effortless. Sam was great, and made this very simple thank you again

TOAR Assessments Since 2009
Credentials Supported