The aim of this book is to make both a theoretical and a practical contribution. On a theoretical level, the contribution concerns an understanding of the evolution of costing, pricing and hospital financing methods. On a practical level, we have applied an action-research approach to calculate the costs of medical procedures performed in medical oncology. Given the two objectives, it was necessary to mobilize a significant theoretical and conceptual framework relating to costing, financing and hospital pricing. This rich and diversified body of literature will subsequently facilitate the application of a costing approach. The aim is to contribute to the definition of an appropriate pricing policy for chemotherapy treatments in medical oncology at Moroccan University Hospitals (CHU), and to the budgeting process for medical oncology patients at the HII University Hospital in Fez. It also aims to enrich cost studies carried out in low- and middle-income countries, in the absence of hospital cost accounting.