A variety of different fluids are promoted to correct hypovolaemia. Apart from the crystalloid versus colloid debate, there exists also a colloid versus colloid discussion as different protein (albumin) and nonprotein colloids (dextrans, gelatins, hydroxyethyl starch preparations) are available for this purpose. The different plasma substitutes largely differ with regard to their composition and their physicochemical properties. All currently used strategies for correcting hypovolaemia have their pros and cons. At present, there is an ongoing interest in the major problems associated with the use of plasma substitutes such as their influence on coagulation and kidney function. There are, however, also some less often addressed questions concerning the use of plasma substitutes that need to be answered. Although nonblood plasma substitutes are often administered worldwide, there is still uncertainty with regard to using them in pregnancy, effects on cross-matching and blood typing, mixing with other drugs, dose limitations, the risk of calcium-containing and potassium-containing solutions, the risk of producing itching, the influence on blood sugar level or whether warming can be done safely. Unfortunately, data to answer these very practical questions are limited or are even lacking for some plasma substitutes. To further increase safety in the treatment of the hypovolaemic patient, all possible problems must be discussed and contraindications of nonblood plasma substitutes must be clearly defined.