AbstractThe trend to deliver drugs to defined areas of the body involves sophisticated carriers systems. In addition to thein vitrodrug release profile one must be aware of thein vivobehaviour of the dosage form and the drug. Gamma scintigraphy is an elegant way to gain insights of the actualin vivodistribution pattern of dosage forms. This technique relies on the use of radioactive tracers included into the medicament and selected so as to enable an optimum detection by a gamma ray camera. The choice of a convenient label enables thein vivodetermination of the targeting of the formulation administered through a large number of routes. The present paper reviews applications of gamma scintigraphy for the evaluation of dosage forms administered by the parenteral, rectal, buccal, nasal, pulmonary, and ophthalmic routes.