Strategy research tends to regard strategic planning as a continuum from the non-existence to the existence of well-established, formal strategic planning processes (Brinckmann et al., 2010; O’Regan & Ghobadian, 2002; Verreynne & Meyer, 2008). Much fewer studies have focused on the role of informal strategic planning (e.g., Berry, 1998; Mazzarol, Reboud & Soutar, 2009; Verreynne & Meyer, 2010), many with the implicit assumption that informal strategic planning is only done when formal strategic planning fails or only during the early stages of a company’s life cycle. In this study we seek to understand the continuous dynamics of formal and informal planning, and the related performance consequences.