This study evaluated the performance of geosynthetic interlayer systems to control reflective cracking in hot-mix asphalt (HMA) overlays and determined the main field conditions that affect their performance. Four interlayer systems, which are utilized in the state of Illinois, were chosen for this study: areatype non-woven fabric interlayer, strip-type non-woven fabric interlayer, strip-type self-adhesive fabric interlayer, and strip-type three-layered composite interlayer. Based on a visual crack survey, the condition of the HMA overlays was evaluated in terms of the extent and severity of reflective cracking. A performance benefit ratio (PBR) was determined to represent the relative performance of an interlayer system. Statistical analysis showed that the PBR of the composite interlayer system is a function of traffic volume, lowest temperature, and joint spacing; the PBR decreases as the traffic volume, temperature, and joint spacing increase. However, the performance of the Geosynthetic interlayer systems was insensitive to all the parameters.