Flow Cytometry is one of the most powerful single cell analysis methods used throughout the life sciences and medicine. Utilising Flow Cytometry we can identify and quantify different from heterogeneous samples, analyse the corresponding state of proliferation or simply detect the expression of fluorescent reporters. Improvements in assay technology are now enabling scientist to detect mRNAs in cells using flow cytometry. We will cover the theory of Flow Cytometry and corroborate this information intensively with the practical issues of the most frequent assays as part of our practical course curriculum.