Abstract: In this study, conducted in Denmark in 1994, a group of 30 patients were treated with both NLP and traditional medical methods and compared with a control group of 16 people who were receiving only standard medical treatments. In addition to the Allergy Process, NLP treatment consisted of the application of Time Line and Change Personal History techniques to address negative emotions; the utilization of Reimprinting and Sleight of Mouth patterns to transform negative or limiting beliefs associated with the patient's past. Other NLP techniques used in the study included Reframing to find the positive intentions and secondary gains behind symptoms and offer other choices; Level Alignment and the Resonance Pattern (finding positive mentors) to strengthen resources; shifting Meta Model patterns and Submodalities to challenge limiting mental models. The selection and use of these techniques varied according to the needs of the patients. The results of the interventions were measured by tracking the patients' lung capacity and their need for medication and hospitalization. Both the group receiving medical treatment only, as well as the group receiving the treatment combined with NLP showed improvement, but there were some significant differences with the NLP group. For example, the lung capacity of adult asthmatics typically decreases 50 ml per year, which was the case with the control group. In contrast, the members of the NLP group actually had an increase in lung capacity of about 200 ml. The rate of hospital admissions was reduced significantly in the intervention group, as was the number of acute, severe asthma episodes. In addition, their consumption of medication was reduced to near zero. Their rate of sleep disorders, caused by asthmatic symptoms, was also reduced to zero (while the control group was only reduced to 30%).