The aim of the present study was to try to understand humor´s function, viewed from a developmental and affect-theoretical perspective, with special emphasis on the shame affect. The methodological approach has entailed a case study, the case of Beatus, which has been a longitudinal attempt based on qualitative interview data collected over a period of 17 years. The findings showed how awareness of humor in relation to the affects´function (appropriateness in time and space) and importance (clarity at the signal level) increased as Beatus grew older. The metaphor "door-opener" is emphasized for humor´s function in relation to all affects, Whereas the metaphor "moderator" refers to humor´s role in balancing the shame affect against the positive affects. The "pendulation function" is stressed. In the theeoretical deicussion, the term "humor-attunement" is coind. This represents a process-related concept, defined as a capacity to share inner affective states, intergrated with a cognitive perception and understanding of humor´s content and form, appropriately timed to the social context. The discussion also advances a line of thought wherein the driving force or motivation is the affect and humor is the consequence, which guides attention in a particular direction. © 2006 Informa UK Ltd All rights reserved.