Opportunistic infections are increasingly becoming a problem in cancer patients amongst whom infection with Nocardia species is particularly difficult to detect due to the capricious natural history of the disease. Three cases of Nocardia infection in patients who had undergone splenectomy for haematological malignancy are presented. These cases illustrate the diverse mode of presentation, the natural history and the difficulties in early and accurate diagnosis of Nocardia infection. Despite the difficulties in arriving at the correct diagnosis, these cases highlight the importance of early institution of appropriate antibiotic therapy. Antibiotics should be given in adequate doses to control the initial infection and be maintained for a prolonged period to prevent relapses.