In order to achieve higher kinetic energy potential through higher wind speed, the trend of wind turbine, especially for offshore, has higher tower and larger head-to-mass ratio due to larger rotor diameter. This results in a lower natural frequency for the structure. For example, the first natural frequency of RNA (Rotor-Nacelle Assembly) configuration of modern offshore wind turbine is low enough with critical velocity of VIV around 4-6 m/s. This means that even at moderate wind speeds, the occurrence of VIV becomes more frequent as the critical velocity decreases. Such first mode VIV can be aided by a damper fitted to the wind turbine. However decreasing natural frequencies also means that the higher modes will have lower critical velocity. In fact, in the investigation conducted in the DFG and CICIND research funded project, with application partners Siemens Gamesa Reneable energy and Ruhr-University Bochum, both first-mode tower VIV and higher-mode tower VIV were able to directly observed in full-scale measurements conducted in Test Centre Østerild under real life conditions. The investigations captured higher cross wind oscillations around critical wind speeds of the tower, and lock-in phenomenon were observed. In addition, the investigation also uses wind pressure measurement, which allows the structural response and vortex shedding load to be investigated simultaneously. It is noteworthy that very few real-life VIV data sets are currently available with complete information on the structural properties and lock-in range. This investigation aims to bridge the gap between VIV in full-scale wind turbine tower and prediction method mostly developed in wind tunnel, and further provide insights of real-life VIV.