Perceptual Control Theory Demonstrations

The following websites provide demonstrations of the mechanism of perceptual control. Repository of computer programs developed by WIlliam T. Powers, referenced in Living Control Systems III. Adam Matic’s demo programs for your browser are […]

Economics & Marketing

Economics & Marketing

To manage a successful business, you need to know what people want, how your business is perceived, and how to deal with people. It’s ripe for a PCT approach! […]

Psychology & Mental Health


In explaining how living things control their perception, PCT is clearly highly relevant to psychology. Contemporary articles are making the case to the wider establishment that closed-loop, circular causality is much closer to how living systems actually function than the approach researchers still use. […]

Sociology & Philosophy

Sociology – a PCT introduction

Sociology involves understanding how people behave in groups, including how they communicate and interact with one another. PCT provides a way to understand how people’s goals operate when in groups, and we can use computers […]

Economics & Marketing

A Multilevel Systems Model of Leadership

Angelo J. KinickiKathryn J. L. JacobsonBenjamin M. GalvinGregory E. Prussia AbstractThis study uses a control theory to develop a multilevel systems model of leadership. The model outlines the processes that senior leaders can use to […]

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Supporting Organizations

Endorsing the IAPCT and Perceptual Control Theory (PCT) We are pleased to showcase organizations that have indicated their support and endorsement of the International Association for Perceptual Control Theory (IAPCT) and Perceptual Control Theory (PCT). […]

MoL accreditation
Method of Levels

MOL accreditation

Since 2021, we have been working on the development of an accreditation procedure for Method of Levels practitioners. Our objective is to shape the procedure according to Perceptual Control Theory (PCT) principles and provide a […]

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BOARD MEMBERS Eva de Hullu Open Universiteit. The Netherlands IAPCT PRESIDENT As assistant professor in the department of clinical psychology at the Open University in the Netherlands, I teach students therapeutic skills, heavily informed by […]

In Memoriam

Martin Taylor

Maurice Martin Taylor died in the afternoon of Friday 17 March 2023, after several months of terminal illness. His 87th birthday was nine months prior, on 14 June 2022. By temperament and by education Martin […]

In Memoriam

Hugh Petrie

Hugh Petrie was a friend and supporter in his positions at Northwestern University, the University of Illinois, and the University of Buffalo, where he was Dean of the School of Education. Bill Powers dedicated Behavior: The […]

In Memoriam

Alice Powers McElhone

Bill’s sister Alice died on 5/22/22 at age 92. I think she might have been amused at the numerical alliteration. Her big brother Bill (1926-2013) was three years older. Her daughter Barbara writes, “Alice ran […]

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In Memoriam

Richard Robertson

Dick Robertson died on 24 March 2022. His son, Eric, wrote to us “in addition to believing in and supporting the work of the Control Systems Group, my Father greatly appreciated and valued the collaboration […]

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In Memoriam

Allison Powers (Allie)

[The following is from Barbara Powers (Bara).] My sister, Alison Mary Powers (Allie) of Lafayette, CO (formerly of Northbrook, IL) passed peacefully in the early hours of January 31, 2021. After a years-long battle with […]

In Memoriam

William T. Powers

Tributes to Bill upon his passing William T. Powers, the engineer/psychologist who developed Perceptual Control Theory (PCT) passed away on May 24, 2013 at the age of 86. He will be laid to rest next […]


Call for abstracts

33rd IAPCT Conference and 2023 Annual Meeting For the IAPCT conference, 12-14th of October 2023 (online), we welcome your proposals for scientific talks, or other kinds of structured, small or large group meetings about all topics […]

Biology & Neuroscience

Perceptual basis of bimanual coordination

Franz Mechsner, Dirk Kerzel, Günther Knoblich & Wolfgang Prinz Mechsner, F., Kerzel, D., Knoblich, G. et al. Perceptual basis of bimanual coordination. Nature 414, 69–73 (2001).

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PCT Conversations

PCT conversations: small online group meetings to discuss topics related to PCT or from a PCT standpoint. Join in to share your questions, ideas, research and experiences with PCT. This can include a broad range […]