The objective of this paper was to analyze the choice of treatment in two-vessel coronary artery disease and to evaluate the effectiveness of the chosen treatment. The data of sixty-five patients with two-vessel coronary artery disease was analyzed. Two-vessel coronary artery disease was recognized when critical stenoses were present in two arteries with a diameter no less than 2 mm across. Patients who had a CABG were excluded. Patients were divided into three groups according to their treatment: those treated with CABG (29 patients), those treated with coronary angioplasty (20 patients), and those treated conservatively (16 patients). The mean follow-up was 29.3 months (12-48 mo). There were two groups of data collected. The first group consisted of data which might have influenced the decision-making and state of the patients after they had been introduced to the selected treatment. The second group consisted of data necessary to evaluate the state of the patients during the follow-up period. The statistical analysis was divided into three stages. In the first stage, clinical data connected to the selected treatments was studied. In the second, the effects of the chosen treatment were examined. During the third stage of analysis, variables which influenced the effectiveness of the specific treatment were evaluated. Decision-making in patients with two-vessel coronary artery disease depended on the co-existence of hypertension, diabetes, lower-limb ischemia and earlier-performed coronary angioplasty. The only statistically important angiographic feature was the condition of the proximal LAD. Objective improvements in the states of patients (evaluated by exercise tests) were frequently connected to CABG treatment. Subjective improvements in the states of patients were more often connected to conservative treatment. Elevated cholesterol levels were connected to the progression of the disease both in those treated conservatively and interventionally.