Henry S. Pennypacker, 1937–2023

Henry S. Pennypacker—“Hank” to all who knew him—passed away on September 12, 2023. His career spanned the evolution of the field of behavior analysis and contributed immeasurably to its progress.

Hank grew up in Missoula, Montana, receiving bachelors and master's degrees from the University of Montana. He studied under Gregory Kimble at Duke University, earning his doctorate in 1962. He then joined the faculty of the psychology department at the University of Florida (UF) and retired there in 1998, although he continued to play an active role in the Behavior Analysis program.

Although he maintained his doctoral focus on classical eyelid conditioning in monkeys for his first few years at UF, he soon began a transition toward behavior analysis, which was gradually acquiring a distinct identity. This conversion was both reflected and facilitated by the addition to the department of Edward F. Malagodi, who had completed his doctoral work at the University of Miami under Dan Cruise. Ed arrived in 1968 with a grant to establish a pigeon lab and a commitment to teach core graduate courses in behavior analysis. Ed's role enabled the beginning of what became the Behavior Analysis program in the department, headed by Hank, one of the earliest in the country and one that continues to this day. Marc Branch soon joined the program, bringing a focus on behavioral pharmacology, and I joined the program in 1975, having completed my graduate studies under Hank in 1970.

Hank's interests in behavior analysis soon took shape. With a commitment to practice in his undergraduate teaching what he preached at the lectern, he began a vigorous initiative to investigate ways of improving student performance to what could justifiably be called mastery level (see Johnston & Pennypacker, 1971). This effort, which was part of the field's growing interest in applying behavior analysis to college-level instructional technology, eventually led Hank to establish a university-wide program involving other faculty and courses, as well as an arrangement with the UF athletic department, which was interested in maintaining the eligibility of student athletes.

His undergraduate teaching efforts were only the beginning of his interest in education, however. In 1969, Hank invited Ogden Lindsley to conduct a three-day Precision Teaching trainer's workshop at UF. This experience cemented a life-long professional and personal relationship with Og, who was in the early stages of developing Precision Teaching and its six-cycle Standard Behavior Chart. Hank coauthored the seminal handbook for the chart in 1972 (Pennypacker et al., 1972), with a second edition published in 2003 (Pennypacker et al., 2003). He remained a leader in the Precision Teaching community throughout his career.

The centerpiece of Hank's literary accomplishments was the publication in 1980 of our textbook on research methods, building on Sidman's Tactics of Scientific Research (1960). We began this project in the mid-1970s with the purpose of addressing measurement practices generally not treated in Sidman's laboratory-oriented book and creating a comprehensive standard for methodological practices in the growing field. Over a 3-year period of daily morning work sessions, we wrote the first edition of Strategies and Tactics of Human Behavioral Research on legal note pads, sharing the drafting of paragraphs and even sentences. It was published in 1980 (Johnston & Pennypacker, 1980). Each of three subsequent editions involved a thorough revision in light of the field's evolution, especially with respect to the increasing influence of credentialed ABA practitioners. The present edition added “practice” to the previous title (Strategies and Tactics of Behavioral Research and Practice) and Gina Green as a third author (Johnston et al., 2020).

As the methods text was taking form, Hank undertook a major initiative that largely continued for the remainder of his career—a research-based development of a technology of breast self-examination (BSE) to detect breast cancer and an approach to transferring that technology on a worldwide basis. As the BSE technology reached fruition, he established Mammatech Corporation as a way of disseminating it to the medical community as well as to women directly. This long-term project generated a number of patents and widely distributed publications and remains the epitome of how to develop and transfer a behavioral technology to the marketplace (Pennypacker, 1986).

These various interests and projects constitute the most notable aspects of his career, but they should not eclipse other activities that have had important and lasting outcomes. In the late 1970s, the Florida Department of Rehabilitative Services established a Peer Review Committee comprised of nationally well-known behavior analysts to monitor the delivery of ABA services to individuals with intellectual disabilities throughout the state. Hank soon became chair of the committee, which conducted annual visits to wide-ranging service delivery facilities that resulted in recommendations for improving services. Over time, this approach was adopted in other states and remains a primary component in how states manage such services.

As part of this initiative, the Florida Peer Review Committee recognized the need for some sort of credential identifying individuals with a certain level of expertise in applied behavior analysis. Hank put together a preliminary credentialing examination that later led to the state contracting for a professionally constructed exam and testing program. This successful state program eventually became the foundation for the Behavior Analysis Certification Board's national credentialing program.

Hank served as chairman of the Board of Directors of the Cambridge Center for Behavioral Studies for many years and received numerous honors and awards, including Fellow of Division 25 of the American Psychological Association (APA), President of the Association for Behavior Analysis, President of the Florida Association for Behavior Analysis, a Lifetime Achievement Award of the OBM Network, a S.A.B.A. Award for Public Service, a Lifetime Achievement Award of the Standard Celeration Society, and the Fred S. Keller Behavioral Education Award from APA Division 25. He served as an editorial board member of the Journal of Applied Behavior Analysis, the Journal of Personalized Instruction, the Journal of Prevision Teaching, The Behavior Analyst, Behavioral Assessment, and Behavior and Social issues.

This superficial summary of Hank's career leaves out what for many colleagues and students were his most memorable qualities. He was both a widely loved colleague and a popular and highly respected teacher at all levels. He had an easy-going personal style that encouraged others to appreciate his observations and arguments. His sly sense of humor was only part of what appealed to students and colleagues. He made the subject matter of his courses and presentations important and inspired others to see how they could make a difference. Henry S. Pennypacker's powerful influence on those who knew him mirrored his enduring influence on our field.