There is a deliberate difference between true will and declaration in the collusive declaration of intent. The declaration of intent must be firstly interpreted in order to determine the effect of the collision on the legal transaction. The validity can be evaluated once the transaction is concluded. In this context, all situations where there is a deliberate difference between will and declaration can be evaluated jointly. In cases where the trust theory is applied, when the addressee of the declaration of intent knows or is able to know the true will of the declaration, such declaration becomes in accordance with the will. In a declaration of will, which does not need to be directed, in which the will theory is applied, the declaration also creates its effects in accordance with the will. In the case of a collusive transaction, the declaration of intent gives rise to no legal effect since the addressee is aware of the true will. In this respect, the reason why the collusive act does not have any legal consequences is that the addressee knows the true will. There is no need for an agreement between parties to prevent the collusive act from having any legal effect. In cases where the declaration theory is applied partially or wholly, any claim arising out of the difference between declaration and true will cannot be heard. The declaration engenders its effects in accordance with its literal content. The declaration gives rise to legal effects in accordance with its content.