Given the important role that physicians play in clinical care, disease advocacy, national health policy making and clinical research, the IMPACT survey sought to assess the attitudes and perceptions of physicians in 3 general categories: diagnosis and treatment of Alzheimer's disease (AD); caregivers and families of patients with AD; and the role of government in dealing with this disease and its consequences. Survey respondents comprised a total of 250 generalists and 250 specialists (neurologists, geriatricians, neuro-psychiatrists, psychiatrists and psychogeriatricians) from France, Germany, Italy, Spain and the United Kingdom. Physicians were aged 25 to 69 years, in practice for between 5 and 30 years and currently spending more than 50% of their time in direct patient care. Results showed that a sizable majority of physicians throughout Europe, specialists and generalists alike, agree that: 1) AD is underdiagnosed and undertreated; 2) patients and families are not prepared to recognise the early symptoms of the disease; 3) early treatment can help to slow the progression of the disease; and 4) more effective treatments are needed. Attitudes were statistically significantly different between some groups of physicians regarding disclosure of the diagnosis of AD, the benefits of lifestyle modification, and the value of AD-specific medication in patients whose symptoms are worsening. Differences in attitudes and perceptions of AD between specialists and generalists were limited; differences between countries were more common and of greater magnitude, particularly with respect to barriers to the use of prescription medications.