Compared to synchronous approaches, asynchronous delay-insensitive (DI) communication links have very interesting and desirable properties with respect to their robustness against timing variations and delay assumptions required to implement them. However, special DI codes have to be used to encode the data being transmitted. These codes are usually prone to transient faults occurring during an ongoing transmission, since, in the worst case, even a single transient fault is sufficient to completely change the contents of a message. Unless further redundant information is provided, the receiver has no means to detect such an erroneous transmission. This can, of course, have severe consequences on a system and the environment depending on it. In this thesis we therefore investigate existing approaches to secure DI communication against transient faults and propose a novel two-step data encoding scheme that combines DI and error detecting codes. Our solution exploits the inherent fault resilience of DI codes to achieve a low overhead and hence good coding efficiency. We use methods from graph theory to analyze this fault resilience and identify appropriate solutions. In contrast to existing approaches we carefully avoid the introduction of timing assumptions to mask faults. The proposed coding scheme is generic and can, in principle, be used with any 4-phase DI code. We give examples on how to apply it to selected representatives of the important class of m-of-n codes and analyze the resulting coding efficiency. Additionally, we provide a metric that allows to identify which codes are well suited for fault-tolerant communication. We, furthermore, provide a range of transmitter and receiver circuit variants that implement the presented coding scheme. In particular, we give detailed gate-level implementation examples for two m-of-n codes, that demonstrate the feasibility of our approach and give some insight into the required implementation overhead.