To cite this version:Swanhild U. Meyer, Michael W. Pfaffl, Susanne E. Ulbrich. Normalization strategies for microRNA profiling experiments: a 'normal' way to a hidden layer of complexity?. Biotechnology Letters, Springer Verlag, 2010, 32 (12) review provides a critical overview of commonly used and newly developed normalization methods for miRNA RT-qPCR, miRNA hybridization microarray, and small RNA-seq datasets. Emphasis is laid on the complexity, the importance and the potential for further optimization of normalization techniques for miRNA profiling datasets.