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Holographic interferometric metrology allows a fast, non destructive and quantitative high resolution full field detection of optical path length changes. Furthermore, by utilization of modern CCD sensor technology and digital image processing algorithms an on-line application of these methods even on biological specimens is possible. In combination with a microscopic resolution this offers new possibilities for the detection of variations of shape, micro movements or refractive index changes e. g. for the marker free analysis of cellular samples. Three holographic interferometric systems for microscopy applications based on digital holography, (speckle) interferometry and photorefractive crystals as holographic recording medium are introduced. Results of investigations on test charts and biological samples to characterize and optimize the lateral resolution as well as the resolution of the detected phase difference changes are presented and discussed. Finally, the applicability of the developed measurement techniques on living cells is demonstrated.