The central thrust of this dissertation is oriented around institutional practices in organizations--i.e., those processes that organizational decision makers take for granted and execute quasi-automatically. My goal is to better understand how such practices emerge and become habitualized over time, how they affect perceptions of the organizational environment, and how they influence organizational success. Specifically, the dissertation analyzes institutional practices as they pertain to (1) routines, (2) trust, and (3) identity.

The first chapter investigates the performance consequences of institutional practices in the form of organizational routines in the domains of alliance management and new product development. I develop the argument that the effectiveness of those routines is highest in "normal" environments but comparatively weaker in both volatile and stable contexts, suggesting an inverse U-shaped moderation effect of environmental dynamism on the link between those organizational routines and competitive advantage. Longitudinal key informant survey data from 279 firms provide strong support for my position.

Chapter two is concerned with how institutional practices affect perceptions of other organizations in the field. Specifically, I integrate a calculative and a relational perspective on institutions to better understand the sources of organizational trustworthiness perceptions. Using the setting of interfirm alliances and based on dyadic survey data from 171 such alliances, I find that the calculative perspective (represented by contractual safeguards) has higher predictive power when the partner lacks a favorable reputation, whereas the relational perspective (represented by organizational culture) predicts trustworthiness more strongly when familiarity with the partner organization is high.

Finally, the third chapter develops a better understanding of how social cognition affects organizational resistance to institutional pressures. A series of experiments shows that perceiving oneself as part of a larger organizational identity reduces participants' tendency to adopt solutions from competitors. I also find that status (low, high) moderates the organizational identity-resistance link. These findings advance our understanding of micro-level sources of organizational action, bring together the highly complementary but thus far largely separate streams of neoinstitutional and identity research, and inform the emerging research stream of behavioral strategy by shedding new light on the role of cognition for strategic action.