Most studies on occupational stress concentrate on chronic conditions, whereas research on stressful situations is rather sparse. Using an event-sampling approach, 80 young workers reported stressful events over 7 days (409 work-related and 127 private events). Content analysis showed the newcomers' work experiences to be similar to what is typically found in older samples (e.g., social stressors, quantitative overload, problems of cooperation). At work and in private life, social stressors were dominant. In multilevel-analyses active coping predicted higher success in calming down and problem solving, particularly in controllable situations. Palliation was positively related to successful calming down and negatively to event-related well-being. With regard to the relationship between chronic conditions and situational variables, (stable) job control was associated with successful calming down in stressful situations, and it buffered the effect of chronic job stressors on successful situational calming down, yielding a specific variant of the demands-control model. Number of work-related stressful events, weighted by significance, was moderately associated with chronic job stressors. However, while chronic job stressors predicted momentary well-being over and above the weighted number of events, events did not predict momentary well-being, and its prediction of stable well-being disappeared once chronic stressors were controlled. These results show how chronic conditions represent background variables that not only have a stronger influence on well-being but also influence the immediate reaction to stressful encounters.