Xavier J. Polk, Ph.D. has been a licensed psychologist in the state of California since 1988. That same year, he founded Behavioral Systems Analysis (BSA) to provide individuals and groups with behavioral services.


Dr. Polk is a hands-on psychologist
who specializes in applied behavior analysis, developmental disabilities,
and the management and treatment
of behavioral problems.


He uses an eclectic treatment approach that addresses the interaction between body, mind, emotion, behavior and
environment. And not only does he address the needs of the individual, he also teaches the people in the
individual's circle of support how to obtain and maintain positive behavioral

Education and Experience

1984 - BA in psychology from the University of Notre Dame in 1974; MA in developmental child psychology from the University of Kansas, Department of Human Development in 1976; and Ph.D. in developmental child psychology from the University of Kansas. 

1981 – 1982, he completed a pre-doctoral internship in developmental disabilities at the University Affiliated Facility, Brown University in Providence, Rhode Island.  

1983 – 1984, he worked at Napa State Hospital in Imola, CA and  Sonoma Developmental Center in Eldridge, CA 1984 - 1994. 

Since 1994, Dr. Polk has been a full time consulting psychologist with BSA.

© Xavier Polk, Ph.D. and Beaury Enterprises Inc 2000