The objective of this paper (part I) is to present a systematic review of bioengineering methods. Next article (part II) will present a list of possible ways of imaging of the Skin surface. In the present paper we discuss methods which assess certain variables, values and properties of slon such as impedance, water output (TEWL), Skin hydration, assessment of water distribution in the stratum corneum, assessment of sebum, assessment of the pH of the Skin surface, partial and transcutaneous oxygen and carbon dioxide pressure, assessment of the elasticity, Skin temperature and smoothness and Skin friction resp. The authors mention also dopplerometric methods, laser-Doppler flowmetry, Skin colorimentry (chromametry, chromatometry) remittance spectrophoto(fluori)metry, Raman's spectroscopy and plethysmography. In all methods basic scientific and practical applications are described. Increasingly there are demand to replace subjective observation, albeit by the experienced eye of the dermatologists, by objective assessment. The demands of research, possibly clinical practice, can be met by a combination of several apparatuses as their properties are complementary.

        Key words: Skin impedance - TEWL - corneometry - subumetry - assessment of pH of slon - thermometry - dopplerometry - plethysmography - Skin colorimetry - remittance spectrophotometry