The classic magistral formulation has a long tradition and is primarily based on empirical evidence. In practice, nearly 50% of the externals prescribed by dermatologists are magistral formulations. It is essential that magistral formulations are adapted to the current state of scientific progress. Obsolete active ingredients must be avoided. The galenic formulation should be optimized. Similar to specialty products, the prescribing physician should be able to rely on the fact that the pharmacological effect of the active ingredient in the base is ensured or at least very likely in the recommended magistral formulations. External bases for specific indications should be purposefully assembled from a scientific perspective. The main focus of the book is targeted therapeutic recommendations under these considerations.