Our concern in this paper is a longstanding one in the field of strategic management-the effect of strategic planning on firm performance. However, we argue that strategic planning is best examined in context of both its formal and informal aspects, as well as with operational planning and technology policy. From a survey of 150 manufacturing firms, planning and performance data were obtained from top managers. Our results provided support for the general argument that both formal and informal planning pay, and that both operational planning and technology policy have significant associations with firm performance. Our concern in this paper is a longstanding one in the field of strategic management-the effect of strategic planning on firm performance. However, we argue that strategic planning is best examined in context of both its formal and informal aspects, as well as with operational planning and technology policy. From a survey of 150 manufacturing firms, planning and performance data were obtained from top managers. Our results provided support for the general argument that both formal and informal planning pay, and that both operational planning and technology policy have significant associations with firm performance.