This is a perennial point of discussion. Leadership and management get very confused.
So here is my offering:
Every group needs leadership, but that responsibility doesn't need to be allocated almost exclusively to one person - everyone has a responsibility to contribute to the success of the group (to be a leader) at times. It is simple, and it works!!
Occasionally a situation arises when someone has to make a decision now - that is a job for the manager.
Most of the time a group simply needs to find (often small) ways to make things easier and better - this is where leadership comes in. The leader is the person who can help the group move forward.
Leadership is a relationship with other members of the group - ideally flexible, dynamic, etc.
- Authority to lead is granted from below by the group.
Management is a role assigned to a person - largely fixed.
- Authority to manage is delegated from above by the organisation.