Edwin H. Friedman was an ordained Jewish Rabbi and a family therapist. He was born in New York City and worked for more than 35 years in the Washington DC area where he founded the Bethesda Jewish Congregation.
His primary areas of work were in family therapy

Family therapy

Family therapy, also referred to as couple and family therapy, family systems therapy, and family counseling, is a branch of psychotherapy that works with families and couples in intimate relationships to nurture change and development. It tends to view change in terms of the systems of...

, congregational leadership (both Christian and Jewish) and leadership more generally.
Friedman's approach was primarily shaped by an understanding of family systems theory. His seminal work "Generation to Generation", written for the leaders of religious congregations, focussed on leaders developing 3 main areas of themselves:

• Being self differentiated
• Being non-anxious
• Being present with those one is leading

Building on his work, "Generation to Generation", Friedman's family and friends published "A Failure of Nerve--leadership in the age of the quick fix" finishing Friedman's work on his understanding of leaders as "self-differentiated or well-differentiated."

Friedman illustrates good “self-differentiated” leadership to that present in the great Renaissance explorers, where leaders had:

• the capacity to separate oneself from surrounding emotional processes
• the capacity to obtain clarity about one’s principles and vision
• the willingness to be exposed and be vulnerable
• the persistence to face inertial resistance
• the self-regulation of emotions in the face of reactive sabotage.

Two concepts are critical in Friedman’s model: self-knowledge and self-control. Friedman attacks what he calls the failure of nerve in leaders who are “highly anxious risk-avoiders,” more concerned with good feelings than with progress–one whose life revolves around the axis of consensus. By self-differentiation, the leader maintains his/her integrity (a non-anxious self as opposed to an anxious non-self) and thus promotes “the integrity or prevents the dis-integr-ation of the system he or she is leading.”

In other places, Friedman argues that well-differentiated leader:

"is not an autocrat who tells others what to do or orders them around, although any leader who defines himself or herself clearly may be perceived that way by those who are not taking responsibility for their own emotional being and destiny . . .
is someone who has clarity about his or her own life goals, and, therefore, someone who is less likely to become lost in the anxious emotional processes swirling about.
is someone who can separate while still remaining connected, and therefore can maintain a modifying, non-anxious, and sometimes challenging presence.
is someone who can manage his or her own reactivity to the automatic reactivity of others, and therefore be able to take stands at the risk of displeasing.