In a large retail business group the ID Migraine Screening Test was sent to employees with three or more absences from work in the past year (n = 2893). Employees with positive results were invited for a neurological consultation and migraine patients were randomly assigned to: first attack 'treated as usual' and the second attack treated with 40 mg eletriptan, or reversed order. Of the 2893 employees, 799 responded (28%), 260 were positively screened for migraine (33%), 84 patients were diagnosed by a neurologist and 41 of the 75 included patients completed the protocol. Eletriptan induced pain-free response in 33.3% of the patients at 4 h compared with 0% after 'non-specific' treatment (P = 0.03). Eletriptan also significantly improved quality of life, but differences in absence from work and productivity loss could not be detected. In conclusion, in-company screening can be beneficial for undertreated employees, but implementation obstacles can reduce the effectiveness of screening.