This article presents a qualitative study and an approach to leadership development based on social constructionism and action learning. We argue that leadership development and leadership identities in postmodern organizations build on negotiation and co-construction of meanings, relations and stories. We investigate the following questions: What happens when a group of leaders from different organizations construct, de-construct and reconstruct their identity as leaders through narrative interviews about their challenges as leaders? In addition, how do these discursive constructions close down or open up for new perspectives, other voices and possibilities for learning and change in their relationships, positions and daily practice as leaders? These questions are examined through an analysis of four narrative interviews with use of outsider witnessing. Finally, we suggest that the notion of co-authoring is a useful concept for developing leadership and leadership identities through reflexive dialogues and emerging stories within the frame of action learning.