This document was written to provide a personal overview of each Marine Officer Military Occupational Specialty (MOS). Its primary purpose is to give Marine lieutenants an overview of officer's MOSs to assist them in deciding their preferences for MOS selection at The Basic School (TBS). The committee members were all Amphibious Warfare Students (AWC-00), Marine captains, with one or two tours experience, and five to eight years in service. Please note: much of the information in this handbook must be taken "with a grain of salt". Although the facts have been checked for accuracy, much of the information contained herein is opinion formed from these officers' personal experiences.