Technical Abstract: Micronaire is a key quality and processing parameter for cotton fiber. A program was implemented to determine the capabilities of portable Near Infrared (NIR) instrumentation to monitor cotton fiber micronaire both in the laboratory and in/near the field. Previous evaluations on one NIR unit demonstrated that acceptable laboratory measurement of cotton fiber micronaire by a portable NIR instrument was indeed feasible. A key component of this program is the demonstration of the robustness of NIR technology and methodology for micronaire measurements through the use of multiple portable NIR analyzers with different measurement techniques. In order to ascertain the robustness of the portable NIR technique, three commercial portable NIR analyzers were compared for instrument agreement of micronaire in the laboratory (laboratory measurement) on a large fiber sample set. Good spectral agreement was observed between the scanning portable NIR units. The preliminary micronaire results for the laboratory trials with multiple portable NIR units were very encouraging, with end-state criteria met for most of the portable NIR analyzers. Measurement time for all units was <3 minutes, and all units were easy to use and operate. Method optimization is continuing.