Several studies have estimated the incidence and prevalence of atopic conditions separately. Relatively few attempts have been made to estimate the extent of co-existence of multiple atopic conditions. OBJECTIVES: To estimate the age-specific incidence and lifetime prevalence of eczema, rhinitis and asthma, alone or in combination. METHODS: Using General Practice Research Database (GPRD), a birth cohort of patients registered with UK general practice within a year following birth and treated in the same practice for the next twenty years was identified. The incidence rate of an atopic condition each year following birth and the lifetime prevalence of each atopic condition alone or in combination with others was estimated.  RESULTS: Among the 3 conditions, eczema had the highest cumulative incidence of 154.4 per 1000 patients (95%CI:153-156) followed by asthma (126.3;(95%CI:125-128)) and rhinitis (60;(95%CI:59-61)), by the age of 20 years. One in three patients diagnosed with eczema and one in six patients diagnosed with asthma had their condition diagnosed by the age of 2 years. Eczema also had the highest lifetime prevalence of clinician-diagnosed disease at 21.1% (95%CI:20.0-21.3) followed by asthma (15.5%;(95%CI:15.3-15.6%)) and rhinitis (9.4%;(95%CI:9.3-9.5)). The median age of diagnosis was 8 years for eczema (IQR:2-20) and asthma (IQR:3-16), and 16 years for rhinitis (IQR:10-25). 36.3% (95%CI:36.1-36.5) of children were suffering from at least one atopic condition and 9.8% (95%CI:9.6-9.9%) were diagnosed with at least two.  About 1.5% of patients were diagnosed with all three conditions. Among these 32%, 30% and 10% had eczema, asthma and rhinitis as their herald condition respectively; the remaining 28% having their first two atopic conditions diagnosed at the same age. CONCLUSIONS: Eczema and asthma showed high co-prevalence and high incidence rates in early childhood. Among patients developing all three conditions, a significant proportion was diagnosed with at least two of them by the age of ten years.  There is likely to be more than one variation of the ‘allergic march’ in those with co-morbid allergic disease.