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Walter Gebhart, MD, Department of Dermatology II, University of Vienna, Vienna (Austria) The past decade’s explosive progress in dermatological research is not only tightly linked to ever improving biochemical, immunological or micromorphological methodology, but also grounded in partnership with rapid and reliable distribution of data at an international level. The paper ‘Idiopathic acquired generalized anhidrosis: Electron microscopic and immunohistochemical studies and analysis of lectin binding pattern of the cell membrane’ by Terui et al. in this issue holds up as an example that this progress is recently expanding from originally epidermisoriented efforts to appendageal structures, and in particular to sweat glands. In fact, a great number of major studies on human sweat glands have been performed by Japanese researchers. Although Kurosumi et al. [1] in their comprehensive review discreetly attribute this circumstance to the frequent excisions of odorous axillary skin in their country, the application of advanced techniques on these samples and continuous monitoring of general knowledge are major impact factors on progress in this field. And undoubtedly, our views upon the structural and functional significance of sweat glands are presently changing. Not only the differences between eccrine and apocrine secretion mechanisms have become vague. The sweat gland organ is also no longer merely a structure destined for cooling and elimination of waste products, but a physiologically most important part of the body participating in essential metabolic, hormonal and immunological aspects of human life as well as in psychosocial communication. Detailed ultrastructural studies have challenged the concept of distinct ‘eccrine’ and ‘apocrine’ secretion modes much more than was thought in the beginning. In secretory coils of’eccrine’ glands, a dark cell type has been found to show exocytotic discharge of granules, apical blebbing and eventually also cellular disruption as seen in typical ‘apocrine’ secretion. Therefore, the classification used in general mammalian biology should also be applied to human sweat glands. The distinction is made on the basis of the gland’s relationship to the skin surface. Typical mammalian sweat glands open into the hair follicle and are thus called ‘epitrichiaΓ (= apocrine or ‘a-gland’). For the primates, however, the characteristic sweat gland type is the tube-like ‘atrichiaΓ (= eccrine or ‘e-gland’). opening freely onto the epidermal surface. Despite serious demands that the terms ‘apocrine’ and ‘eccrine’ should be discarded [2], they are still widely used and well understood even though they are only established names. The morphology of human atrichial eccrine glands has been extensively studied in all its complicated 3-dimen-sional coiled or straight portions and excellently reviewed by Hashimoto et al. [3] in 1986. Five major portions have been identified and each section seems to be attributed to different functions. The secretory coils contain clear serous cells and a luminal rim of dark mucoid cells. Myoepi-thelial cells form a surrounding layer, which fades away as the coil passes over into the transitional portion. This first part of the dermal duct still seems to produce some