Advances in medical care have led to an increasing number of immunocompromised travellers. Travellers with immunodeficiencies have a higher risk of infections and can acquire infectious diseases that are rare in immunocompetent travellers. Of central interest are travellers' diarrhea, diseases of the respiratory tract, tuberculosis and inhalative mycoses as well as diseases transmitted by vectors such as malaria. For every such journey a timely consultation in travel medicine is indicated. First the individual risk must be assessed according to the degree of immunodeficiency. An individual counselling is then related to the itinerary, the travel destination and any activities planned. This information is the basis for an individual set of prophylactic measures with respect to infections and other risks through certain modes of behavior, medication, and vaccinations. Post-travel counselling and evaluation are equally important. This requires physicians experienced in both immunosuppression and travel medicine.