The double barrier resonant tunneling diode (DBRTD) is one of several devices currently being considered by the semiconductor industry as a replacement for conventional very large scale integrated (VLSI) circuit technology when the latter reaches its currently perceived scaling limits. The DBRTD was one of the first and remains one of the most promising devices to exhibit a room temperature negative differential resistance (NDR); this non-linear device characteristic has innovative circuit applications that will enable further downsizing. Due to the expense of fabricating such devices, however, it is necessary to extensively model them prior to fabrication and testing. Two techniques for modeling these devices are discussed, the Thomas-Fermi and Poisson-Schroedinger theories. The two techniques are then compared using a model currently under development by Texas Instruments, Incorporated.