The establishment of a public key infrastructure (PKI) in mobile ad hoc networks (MANETs) is considered a difficult task because of the intrinsic characteristics of these networks. The absence of centralized services and the possible network partitions make traditional security solutions not straightforwardly applicable in MANETs. In this paper, we propose a public key management scheme based on a binary tree formation of the network¿s nodes. Using the binary tree structure, certificate chains are easily built between communicating nodes that are multi-hops away and the cumbersome problem of certificate chain discovery is avoided. We argue that our mechanism has several advantages over similar solutions, especially when a fair balancing between security and performance is terminus.