In the case of COPD, clinical practice guidelines are not adopted as recommended. Improved patient care may be gained by determining the barriers to implementing these guidelines. It is important to determine whether patient and prescriber factors are the primary barriers to the use of pharmacotherapy. An analysis of retrospective cohorts was used in this study. Health maintenance organization members diagnosed with stage 2 to 4 COPD based on spirometry. Medical records were reviewed in order to determine if: 1) patients had affordability issues, 2) they had adverse drug reactions, 3) they had an ineffective therapy, and 4) they had prescription histories. It was determined that 55 medical records had been reviewed. Patients with non-completion of guidelines-recommended medications during the previous year accounted for 50% of the total and 44% did not have medication prescribed according to guidelines. Ineffectiveness and affordability issues were documented in only 4% and 2% of patients, respectively. Neither adverse reactions nor drug interactions were reported. Researchers observed a positive relationship between patients' acceptance of COPD treatment recommendations and their providers. There are still a number of barriers to COPD treatment that need to be reduced and interventions need to be developed to alleviate thes