Wind turbines are often the highest features on a landscape making them susceptible to lightning strikes. Electronic and electrical equipment mounted the blades, nose, hub, nacelle, tower – even at the base – are exposed to lightning and other over-voltage transient sources. This paper provides the basics of how the IEC and IEEE methods quantify the threat. It also provides an overview of four main technologies used in surge protection devices along with standards and tests applicable to them. The paper also addresses the importance of proper grounding and the effect of high-resistance grounds on the performance of surge protection devices. Turbine manufacturers and owners can use these concepts to increase the lightning protection of existing turbines.