The purpose of the present article was to provide a reasonably coherent picture of the concept as well as the prediction of the misunderstood phenomenon of orthodontic cooperation. A sample of seventy orthodontic patients was studied. A double-blind quasi-experimental research design was performed. Psychological instruments were used in order to measure achievement, affiliation, and attribution motivation. The following dependent variables were recorded: headgear wear, elastic wear, appliance maintenance, nonbroken appointments, oral hygiene, and plaque index. The raw data were analyzed by three different techniques. The results obtained from this study indicate that orthodontic cooperation is predictable through psychological testing. Specifically, high-need achievers cooperate better orthodontically than low-need affiliators, and internals cooperate better orthodontically than externals. Further, it was found that orthodontic cooperation does not involve a simple single general dimension of cooperation. Rather, orthodontic cooperation is composed of a more complex structure of two orthogonal constructs: Specific Orthodontics Construct of Cooperation (SOCC) and Perio-Orthodontic Construct of Cooperation (POCC). Because SOCC and POCC are orthogonal, a patient who is a good brusher does not have to be a good headgear wearer, and vice versa. The relative contribution of motivational psychology on each of the variables constituting orthodontic cooperation was determined. The implications for clinical applications were presented.