What does a Ship Broker do?

A broker is an individual or party that brings together and arranges transactions between a buyer and seller for a commission when the deal is executed. In the shipping industry, brokers are intermediaries between ship charterers (buyers) and ship owners (sellers).

• Make initial contact with charterers and owners
• Match ship charterers and ship owners
• Assist with drafting of agreements and associated negotiations
• Advise client during preliminary stages of proposal
• Curtail potential disputes & costs
• Iron out stumbling blocks to deals
• Facilitate client's understanding of documents & points of concern
• Pin-point where legal advice is necessary
• Provide market intelligence

How can ship brokers add value?

• Match ship owners with shipyards (where ships are built and repaired)
• Assist ship owners in shipyard selection
• Contribute expertise by advising in ship design stage
• Ensure FAIR principles are applied when facilitating charter negotiations between ship owners and ship charterers. Note that FAIR does not mean equal.
• Fair & realistic distribution of risk in proportion to relative rewards
• Allocate risk to party best placed to assume it
• Insure: Sufficient scope of cover
• Reasonable: Avoid "duplicate" assumptions of risk & minimise potential for dispute 

Sources:
http://en.wikipedia.org/wiki/Broker
http://www.slideshare.net/m3marinegroup/020812-11522704