This paper proposes and evaluates strategies to build reliable and secure wireless ad hoc networks. Our contribution is based on the notion of inner-circle consistency, where local node interaction is used to neutralize errors/attacks at the source, both preventing errors/attacks from propagating in the network and improving the fidelity of the propagated information. We achieve this goal by combining statistical (a proposed fault-tolerant cluster algorithm) and security (threshold cryptography) techniques with application-aware checks to exploit the data/computation that is partially and naturally replicated in wireless applications. We have prototyped an inner-circle framework with the ns-2 network simulator, and we use it to demonstrate the idea of inner-circle consistency in two significant wireless scenarios: (1) the neutralization of black hole attacks in AODV networks and (2) the neutralization of sensor errors in a target detection/localization application executed over a wireless sensor network.