The contract is on the basis of a comparative base effect of the contract stipulates that the effects of the contract go off limbs, without extend to others, as hard as an asset in the impact of actions in terms of the people is the relative, the others here is not affected by what is stated in it from the effects, The implementation of the contract may be limited the contractors just as if they were outlets for it , however, that this rule not a obstacle to possibility of the departure of effects to the contract to the third party, but the intervention of non-contracting has become possible, through reference to the subject of the contract without invoking or invoked , which gives this third parties the possibility of intervention by his appearance at a later stage as a party in the implementation of this contract, however, the same time we may find that the character of a contractor or one of His attributes irrelevant to the other Contracting , since the latter has contracted on the basis of very purports to achieve this decade, to see that this idea does not preclude such an intervention, as it may get a conflict between the availability of account personal element and implementation by non-contractor, and that it is possible to raise this conflict and then the possibility of execution of the contract by a non-contracted personally. .