The main resarch in sensor networks has been focused on minimizing power consumption of sensors to maximize network life time. In some critical applications, however, the most important issue is to transmit sensing information to the end user (the sink node) with reliability. Reliable information forwarding using multiple paths in sensor networks (ReInForM) can achieve desired reliability in the error-prone channel, but it needs increasing transmission overhead as the channel error rate becomes high and the number of hops between the source node and the sink node increases. In this paper, we propose reliable transmission using intermediate source nodes in sensor networks (ReTrust) to reduce packet overhead while keeping the desired reliability. Intermediate source or sink (IS) nodes between the source node and the sink node are set and they play a role as intermediate source/sink nodes. The IS nodes should be determined so that the given transmission reliability is satisfied while red...