Volume therapy is an essential component of the daily tasks in routine clinical practice, since the overwhelming majority of surgical, trauma and intensive care patients receive intravenous fluid administration during their inpatient treatment. The range of all these intravenously administered fluids is varied. There are crystalloid solutions with a balanced and non-balanced composition, as well as colloid solutions with hydroxyethyl starch, gelatin or dextran with varying concentrations and compositions of the crystalloid carrier solution. The physicochemical characteristics of colloidal macromolecules determine their volume effectiveness and side effect profile. All these substances are presented in this textbook and their features are described in order to facilitate therapeutic decision-making for the reader in daily practice.