The motivation for the work presented in this paper stems from the observation that optical token-ring networks have bit-error rates that are low enough to be negligible for all but the most demanding applications. We define the notion of careful protocols that attempt to benefit from the reliability of such networks. Although it might seem trivial to implement protocols in the presence of a reliable network, a closer look reveals that this is not at all true. In essence, while protocols based on unreliable networks have to worry recovering from lost packets, careful protocols have to worry about flow-control. This is work in progress, and as such, incomplete. However, first results appear to show that it might be worthwhile to use careful protocols over networks with high reliability.