Summary. Shared leadership as part of modern transformational leadership style has proven to favorably influence team effectiveness and the achievement of an organizational balance between opportunity-seeking and advantage-seeking innovation, which positively impacts company performance. Mastery goal orientation (i.e., learning and development) rather than performance goal orientation (i.e., competition and social comparison) results in better group performance as required to solve complex problems. Therefore, questioning hierarchy and leadership is critically important to improve teamwork. High professional identification and altruistic and service-oriented goals are necessary for the successful development of collaboration competency and collective leadership.
Shared Consensus in Decision-Making in Animal and Human Studies
Unshared consensus and single leaders were assumed to be the norm in species like macaques and horses. However, studies have found that, in fact, also these animals take decisions based on consensus shared among group members . In human leadership research, shared leadership (including collective and distributed leadership) as part of modern transformational leadership style evidently has a positive effect on team effectiveness . Indirectly through the creation of organizational adaptability that enables finding the balance between opportunity-seeking and advantage-seeking innovation, shared leadership favorably influences company performance .
Leadership Style Depending on Relational Trust and Goal Orientation
In healthcare, flat hierarchies and shared decision-making structures that empower leaders on all levels, are suitable strategies to add to patient safety and employee well-being ; . Learning is another area for which collaboration is beneficial . Although the most effective way to enhance student achievement is the creation of professional learning communities, many middle schools still focus on managing test scores instead of enabling team learning processes in a collaborative learning environment . Regarding tensions between official functions and citizens, for institutions like police departments, transformational leadership with a shared cooperative vision is imperative .
Trust was found to increase the likelihood of collaborative engagement between teachers , and to be a success factor for re-culturing schools . Trust seems to be the necessary condition to enable the exchange of knowledge . Shared information and knowledge elaboration allow diverse groups to develop practical solutions to challenging problems . As studies in groups of children showed, leadership styles may depend on whether set goals are related to learning and development (mastery goal orientation) or competition and social comparison (performance goal orientation). Mastery orientation proved to contribute positively to shared responsibility and resulted in better group performance (i.e., solving a complicated math problem) than the performance condition in which lack of communication, member dissonance, and exclusion led to the use of forceful domination instead of cooperative leadership .
Challenging Hierarchy and Leadership to Improve Teamwork
Besides individual characteristics such as enthusiasm, vision, and knowledge, organizational culture, political situation, and member composition are influential factors for the development of shared leadership capacity . Questioning hierarchy and leadership to improve teamwork  may be necessary but also challenging within traditional settings . Group processes can be problematic for individuals who are used to concentrate high power . Low professional identification as well as weak focus on, for example, patient safety or student success hinders support for shared leadership too . Not insisting in mere self-reliance in information elaboration  and valuing altruism and service towards others are critically important for the successful development of collaboration competency and collective leadership .
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