Employees in many contemporary organizations work with flexible routines and flexible technologies. When those employees find that they are unable to achieve their goals in the current environment, how do they decide whether they should change the composition of their routines or the materiality of the technologies with which they work? The perspective advanced in this paper suggests that the answer to this question depends on how human and material agencies—the basic building blocks common to both routines and technologies—are imbricated. Imbrication of human and material agencies creates infrastructure in the form of routines and technologies that people use to carry out their work. Routine or technological infrastructure used at any given moment is the result of previous imbrications of human and material agencies. People draw on this infrastructure to construct a perception that a technology either constrains their ability to achieve their goals, or that the technology affords the possibility of achieving new goals. The case of a computer simulation technology for automotive design used to illustrate this framework suggests that perceptions of constraint lead people to change their technologies while perceptions of affordance lead people to change their routines. This imbrication metaphor is used to suggest how a human agency approach to technology can usefully incorporate notions of material agency into its explanations of organizational change.