This study examined the relationship between life events and experiences, psychological adjustment and upper respiratory illness in 78 children, age 7-14 years, with moderate to severe asthma attending a specialist children's asthma clinic. Longterm experiences (LTEs) and acute life events (LEs), both positive and negative, were evaluated at baseline and after 9 months using an interview-based measure of psychological stress: PACE (Psychosocial Assessment of Childhood Experiences). Psychological adjustment was measured using Speilberger's State-Trait Anxiety in Children questionnaire and Harter's Self-Perception questionnaire. The occurrence and severity of upper respiratory (UR) symptoms were recorded daily by the parent using a specially designed symptom diary. At times of increased UR symptoms parents contacted the researcher who arranged to collect a throat swab for subsequent viral analysis. A mean of 2 upper respiratory infections (URIs) per subject was recorded over the study period with a mean of 1.7 UR symptoms per day on 27% of study days. Girls, age 9-11 years, were at increased risk of reporting higher levels of URI (p < 0.05). Children in lower social class groups were at increased risk of reporting higher levels of high negative LTEs (p < 0.05) and lower levels of positive LTEs (p < 0.001) compared to those in higher groups. High threat LTEs were negatively related to symptom measures in boys (r = 0.37, p < 0.05), with positive LTEs apparently playing a protective role. Those with high mean UR symptoms were at increased risk of reporting a higher number of high threat LTEs compared to those with low (p < 0.05) or moderate UR symptoms (p<0.05) Self-perception scores were significantly higher in children with asthma compared to a normative Scottish sample of schoolchildren. Reported mean UR symptom levels were negatively correlated with self-perception scores but not anxiety measures. Boys reporting high mean UR symptoms perceived themselves as less well-behaved and had a lower sense of their own global self-worth compared to those with low UR symptom levels but after controlling for high threat LTEs (mean duration 40.9 months), this relationship disappeared. Girls, particularly those aged 9-11 years, were at increased risk of reporting acute high threat LEs in the 6-week period before the start of a URI. These findings show that high chronic stress levels are related to UR symptoms in boys with asthma, a relationship that might be moderated by self-esteem and mediated by inappropriate behaviours such as non-compliance with medication. In contrast, girls were at increased risk of URI or cold after the occurrence of an acute high threat life event.