Open distributed environments require that agents who are not known to each other must be able to interact. A new authorization scheme called trust negotiation has emerged allowing two strangers to iteratively and bilaterally establish trust. This scheme has been applied to different environments such as the Web, P2P networks or Grid environments. However, it is not yet clear what impact, implies its integration into running systems what leads to a lack of adoption. This papers investigates the overload produced by the integration of trust negotiation techniques and shows how negotiations might, under some assumptions, imply only a small increase on the network use in comparison with the benefits it provides. 1