Experiences of current and career professional development were surveyed fo
r about 3,900 psychotherapists at all career stages in several western coun
tries. Participants included psychologists, psychiatrists, and other mental
health practitioners representing a broad range of theoretical orientation
s. Measures of experienced development were consistent across professional
and demographic categories. As expected, perceived therapeutic mastery incr
eased with increasing years in practice, but currently experienced growth r
emained at a high and unexpectedly constant level across career cohorts, in
cluding the most senior practitioners. Overall findings suggest that therap
ists experience development simultaneously as a gradually increasing sense
of professional expertise and as an ongoing sense of continual improvement,
interpreted as essential to maintaining their motivation and morale. Contr
ibutions of these aspects of therapist development to process and outcome a
re discussed.