The aim of this paper is to describe and analyze a theatre fragmentutilizing the concept of forms of vitality as proposed bydevelopmental psychologist Daniel Stern. The selected fragmentbelongs to the play Krapp?s Last Tape by Samuel Beckett. Threeperformances of it, each by a renowned actor, were subjected to anELAN program. A comparative analysis was made using an ad-hocobservational code containing four categories: forms of vitality in theactor´s movements, voice, scene sounds other than voice, andlighting. Subcategories were created based on attributes described byStern (i.e. sudden, gentle, effortful), and were assigned along atemporal line. Prevalent forms of vitality per category were identifiedin each case, plus a comparison between categories. Finally, adescription of the effect of these different display and combination offorms of vitality on the experience of spectators is discussed