Parallelism can use existing technology in computer communications network design to provide higher data rates and a greater degree of flexibility than monolithic systems. This research investigates the design of a high-speed Parallel Local Area Network (PLAN) interface. It defines the goals of a PLAN interface as low data latency, high data throughput, scalability, and low cost. Three fundamental PLAN interface categories are proposed to meet these goals. These categories are single-bus, dual-bus, and bus-free adaptors. The relative merits of each category are discussed in terms of suitability to several adaptor applications. Each category is further explored by developing a VHDL model of a representative system. The latency, throughput, and component utilization of each model is measured. For medium to large data sets, the dual-bus design provides slightly greater throughput when transmitting encoded data. When transmitting medium to large unencoded data sets, the bus-free design yields marginally higher throughput. In nearly all cases the bus-free design has a greater latency than either of the bus-based design options. Other insights gained from the models regarding physical construction of each adaptor type are also presented.