International travel, including patients travelling with diabetes mellitus, is predicted to increase in the coming decades. These patients will require pre-travel education regarding adjusting insulin and oral antidiabetic agents during their journey especially if they fall ill. The spectrum of travel-related illnesses includes food and waterborne diseases, airborne and vector-borne diseases, zoonoses, sexually transmitted and blood-borne diseases, and diseases transmitted by soil. This article reviews the pre-travel vaccines and immunisations and infectious diseases of potential risk to diabetic travellers. Furthermore investigation of fever in returned diabetic travellers with particular reference to physical signs of common tropical illnesses is also discussed.