The New Mexico State Highway and Transportation Department began an in situ cold recycling (ISCR) program in 1984. On more than 1,850 lane-mi of Interstate, primary, and secondary highways, this effort has been successful in reusing valuable resources (asphalt and aggregate), reducing the transportation and handling of materials, minimizing environmental pollution, and rehabilitating pavements with many types of distresses at minimal cost. The development of the ISCR design, specification and construciton methods, and the selection of high float styrene-butadiene-styrene polymer-modified emulsions to overcome many of the problems (rutting, reflective cracking, and moisture damage) previously encountered with conventional rejuvenators are discussed. Annual statewide tours of ISCR projects have documented overall excellent rideability, minimal rutting, and a delay of reflective cracking by 5 to 6 years over that in control sections.