In certain cases where you have repaid some installments of a previous student loan independently, you would be given the authority of branching away the Co-borrower. This is known as Co-Borrower Release and by doing so, you ensure that the loan repayment is entirely yours. This also puts you in a position where you are not hit by the Credit History of your Co-Borrower. Both of you are separate entities speaking from the loan perspective and you would hence need to take charge of repaying your loan off.
Loan agreements fall into two main types, according to the type of lender, and according to the type of facility. With respect to the type of lender, there are bilateral loans and syndicated loans. Syndicated loans are provided by groups of lenders, and their structuring and arrangement, as well as their administration, are carried out by more than one bank, commercial or investment ones, and the lending banks are also referred to as arrangers.
"Investment banks" create loan agreements that cater to the needs of the investors whose funds they attempt to attract; "investors" are always sophisticated and accredited organizations not subject to bank regulatory supervision and the need to cater to the public trust. Investment banking activities are supervised by the SEC and their main focus is on whether the correct or proper disclosures are made to the parties who provide the funds.
Prior to entering into a loan agreement, the "borrower" first makes representations about his affairs surrounding his character, creditworthiness, cashflow, and any collateral that he may have available to pledge as security for a loan. These representations are taken into consideration and the lender then determines under what conditions (terms), if any, they are prepared to advance money.