An experiment tested the hypothesis that when subjects who display the Type A coronary-prone behavior pattern are placed under stress, they prefer to wait for the stressful event with others, but desire to work under stress alone. One half of 25 Type A and 25 Type B (non-coronary-prone) subjects were told that they would receive painful electric shock while working on a mental task, while the other one half were told that they would receive subliminal stimulation. Both groups were then given the choice of waiting for the event with others or alone and the choice of working on the task alone, in the company of others, or in a leader-directed group. The results showed that Type As relative to Type Bs tended to wait in the company of others regardless of threat level, but displayed a marked preference to work alone under high threat. This decision to work alone was not influenced by waiting preference. Subsequent correlational studies showed that coronary patients (n = 40) reported a greater preference for working alone when under pressure than matched controls (n = 40), as did Type A college students (77% vs. 14% for Type Bs) when asked their preference within the context of the structured interview that is used to assess the Type A pattern. The significance of the findings for increasing the understanding of affiliative preferences and coronary-prone behavior are discussed.