Security-trusts are the most effective securities that a creditor can hope to obtain from his debtor. They grant to the creditor, not a simple right of preference but an exclusive right over the object of the guarantee. The exclusivity conferred by property allows the creditor to guard against the default of the debtor and places him out of competition from other creditors. The use of these securities is much simpler, faster and more efficient than that of traditional securities. Except in cases limited by the rules of possession and good faith, creditors holding security-trusts are generally disinterested, even in the presence of seizure or bankruptcy proceedings initiated against their debtor. Security-trusts appear as the suitable mechanism that can provide the security sought by lenders and promote the granting of credit. However, the legal regime of turkish security-trust is still very incomplete. The rules of constitution handicap the attractiveness of these credit instruments. Security-trusts do not yet ensure a perfect balance between the interests of the parties. However, because it benefits from more recent rules taking into account the major interest which consists in the balance of powers between the parties, because it also benefits from effective publicity and more flexible constitution conditions, the leasing can be an example to follow in the adoption and revision of the legislation brought to trust-security and retention of title. Swiss and french legislation can also enlighten the legislator in the context of a reform to be considered in turkish law. In any event, it is evident that the attractiveness of security-trust can’t be ensured under turkish law without legislative intervention.