The functions and workload of medical oncologists are becoming increasingly relevant as cancer is a priority health issue in our country. Taking into account the specific characteristics and complexity of caring for cancer patients, the time of physicians attached to Medical Oncology could be distributed as follows: 70% for consultation (including participation in tumour committees and multidisciplinary units), 15% for research and 15% for training, teaching and clinical sessions. The time distribution for Heads of Services or Heads of Units is different, since it must also include their clinical management tasks, team coordination, and relations with other services and institutions. The average time, calculated in minutes, spent on each activity per patient is as follows: first visit and “second visit or results visit” 60–90 min; successive visits at the day hospital 15 min; successive visits of patients for follow-up or checkups 20 min; visits with family members 15–20 min; telephone or e-mail consultations 5–10 min; hospitalisation 20 min; and interconsultation 30–60 min. Also, participation in multidisciplinary committees takes up 60–120 min of an oncologist’s time each week. When new technologies such as electronic medical records, e-mail and other software are used, these times increase with a correction factor that is still to be defined and which could vary according to the centre. Finally, the ratio recommended by SEOM is one medical oncologist for every 83 new patients a year.