His published works examined and explained how managers in profit and non-profit organizations behaved under certain situations and conditions.
[2] He put forward that there was only one realistic and unambiguous definition of managerial effectiveness, the extent to which a manager or leader achieves the output requirements of the position.
Reddin was often quoted as saying both in his writings, to his clients and to his students, that there is no ideal style of managing; and there is no one way to make an organization more effective.
[5] This concept of managerial effectiveness is the central issue of Reddin's research, teachings, writings, diagnostic material and in his consulting and training.
Where Bill Reddin maintained that managerial effectiveness is defined in terms of output rather than input, meaning what they achieve rather than what they do, his colleagues in behavioralist studies and human psychology held that there were indeed ideal styles of management behavior.
Due to the war years, the early part being an evacuee then the loss of the family home during an air raid, he experienced many schools in several different towns.
He held various jobs during this time from street sweeping to a lab assistant until he joined the Canadian army as a radio operator - signal man.
During these years in university he continued working odd jobs saving enough money to attend Harvard Business School.
[7] In his two years at Harvard Business School he was dismayed that they were assigned only one book on exploring organization and people which was Carl Roger's Counseling and Psychotherapy.
It was at MIT that he began to evolve his theories on managerial effectiveness interwoven with the responsibility of an organization's impact on society or the social system it served.
In his seminal article, Any Manager's Responsibility he explained his thinking in the opening paragraph: In 1965, Reddin joined the faculty of the University of New Brunswick Business School.
His home in Fredericton served as a forum for students and scholars to discuss ideas and issues governing management and organizations.
He maintained that managerial styles are best understood in relation to specific situations, to the effectiveness it had on advancing the goals and success of an organization.
At the heart of the 3D Theory there is a simple idea, he wrote, which he discovered through a long series of research studies, and in close collaboration with key thinkers and teachers and writers on organizational development and psychology.
Reddin's work and that of his writing and research fused his foundational theory that it is every manager's job to make the organization more effective ensuring the right results are generated.
He was drawn to the thinking, writing and work of number of critical colleagues and teachers who in turn influenced his understanding of people and organizations.
Bill Reddin's Model of Managerial Effectiveness is a practical application of Peter Drucker's (1909–2005) theories of Management by Objectives.
Drucker coined the concept of knowledge workers and the overarching emphasis on effectiveness especially among the executive strata of an organization by being objective oriented.
A perceptive observer of behavior, Drucker recognized that in the daily churn of work, employees become so focused on the job at-hand they forget why they're doing it.
"Objectives are needed in every area where performance and results directly and vitally affect the survival and prosperity of the business, wrote Drucker, and the first requirement, he continues, … in managing managers is by objectives…"[22] With MbO, employees participate in establishing and setting goals with performance evaluations stemming on how they fulfill those goals.
"[23] Reddin put forward that effectiveness of knowledge workers can be measured by looking at the position held by the manager and the demanded impact of that role: what outputs are required.
Of his many accomplishments and significant positions he held over his lifetime, he served as director of the Center for Group Dynamics at MIT where Reddin eventually did his post fellowship.
While working at MIT in 1946, Lewin examined issues governing prejudices and set up a workshop to conduct a 'change' experiment.
Lewin's studies and work on leadership climates, and, on the change process also deeply influenced Reddin's research and future writings, training and development of his diagnostic material on effectiveness.
Lewin's early model of change was described it in terms of a three-stage process, and served as a corner piece to Reddin's work on helping managers and leaders become effective.
In Lewin's change model he called the first stage unfreezing involving overcoming inertia and dismantling an existing mind-set.
Change occurs at the second stage — this is a period wrought with confusion as the individual transitions from a previous mind-set to a new way of looking at and thinking of things.
The final stage is when the individual understands clearly what needs to change and establishing a comfort level going forward forming a new mind-set.