The lack of fundamental OD research has underscored the need for a model of planned change. Because of the lack of a generic model, change process and intervention theories are “recklessly combined and cross levels of abstraction, levels of analysis, and narrowly defined discipline boundaries. The purpose of this section is to present a model of planned change that attempts to provide a framework for integrating OD theory, research, and practice. The Porras and Silvers model of planned change provides a useful framework for introducing change within an organizational setting (see Figure 14-1). Specifically, it addresses how planned interventions targeted at specific organization variables will result in positive organizational outcomes. These are four distinct parts to this model. First, it distinguishes two types of intervention strategies-OD and organization transformation (OT). Porras and Silvers feel that OT should be a separate entity because the underlying theories and concepts are not as well defined as OD. In comparison, human process-based and techno structural theories have gained widespread acceptance among OD practitioners.