Measurement of the W boson mass at LEP

The mass of the W boson has been measured by all LEP experiment by the method of diret reonstrution in the WW deay hannels where at least one W boson deays hadronially. This preision measurement is inuened by many systemati unertainties whih were extensively studied. One example is the possible eet of Colour Reonnetion between the deay produts from dierent W bosons in fully hadroni WW nal states. These proeedings overview the preliminary results onerning the W mass measurement and the ongoing measurements of the Colour Reonnetion eet.