Because the choice of leadership structure is nonrandom decision, this study employs a two-step procedure proposed by Heckman (1979) to investigate the role of external competition, board characteristics, and ownership structure on the choice of leadership structure, and to examine the relationship between dual-leadership structure and firm performance. The results show that the choice of leadership structure is endogenous. In a rapid growth environment and under high product-market competition, firms tend to adopt a dual-leadership structure because this structure can enhance competitiveness and enable firms to adapt to environmental dynamism. In addition, firms with a large board, high director ownership, high managerial ownership, or high institutional shareholdings are less likely to adopt a dual-leadership structure in order to avoid assigning too much power to the CEO. The results also show that the relationship between dual-leadership structure and firm performance is insignificant; thus, the relationship is not necessarily a positive or negative. Instead, the choice of leadership structure enables responsiveness to the external environment, internal governance mechanisms, and firm characteristics.