Impeccable sample fixation is a prerequisite for a correct histological diagnosis. Tissue samples must be immersed in an optimally chosen fixative immediately after sampling, because a timely fixation will prevent autolysis, putrefaction and other unwanted cellular alterations. The fixative alters the tissue by stabilizing proteins and making them resistant to further alterations. It also has to alter soluble cell components into insoluble cells in order for those components to be preserved in further processing. That alteration is called denaturation and it can be conducted chemically (fixative solutions) or physically (heat, drying). If fixated properly, the tissue sample can withstand additional histological tissue processing and staining. BioGnost’s Bouin’s solution is an excellent choice for tissue samples to be stained using trichrome methods and for preservation of soft and delicate structures. It is especially useful as a fixative for tissues with chromosomes in stages of mitosis and meiosis being observed because it preserves nuclei and chromosomes exceptionally well.