This investigation involved a theoretical and experimental study of space-dependent reactor transfer functions with temperature feedback. The reactor transfer function under investigation was the neutron flux response to an input perturbation or source. An existing theoretical model, known as the complex source method, was extended to include temperature feedback effects and the resultant equations were programmed for a model of the Georgia Tech Research Reactor (GTRR). Spatial transfer function measurements were made in the GTRR using an in-core pile oscillator employing a pseudo-random binary sequence. Several detector locations were investigated for both zero-power and at-power (900 kW) conditions over a frequency range from 4 × 10−4 to 8.5 Hz. Data were taken and stored on magnetic tape using two PDP-8 computers and a magnetic tape unit. The theoretical calculations and the experimental results agreed quite closely. Temperature feedback effects for the GTRR were observed to occur at frequencies of 2 × 10−2 Hz and lower, and to become quite pronounced below 1 × 10−3 Hz. Spatial effects were observed to be significant only for frequencies above 1 Hz. The agreement of the calculations with the experimental results served to validate the theoretical model.